Molecular Motor Proteins
Kinesin
Myosin Type V
Dyneins
Microtubules
Myosins
Evoked Potentials, Motor
Motor Cortex
Optical Tweezers
Myosin Type I
Microtubule-Associated Proteins
Myosin Heavy Chains
Movement
Cytoplasmic Dyneins
Hair Cells, Auditory, Outer
Adenosine Triphosphate
Motion
Actins
Myosin Type II
Models, Biological
Axonal Transport
Spindle Apparatus
Protein Transport
Adenosine Triphosphatases
A processive single-headed motor: kinesin superfamily protein KIF1A. (1/1515)
A single kinesin molecule can move "processively" along a microtubule for more than 1 micrometer before detaching from it. The prevailing explanation for this processive movement is the "walking model," which envisions that each of two motor domains (heads) of the kinesin molecule binds coordinately to the microtubule. This implies that each kinesin molecule must have two heads to "walk" and that a single-headed kinesin could not move processively. Here, a motor-domain construct of KIF1A, a single-headed kinesin superfamily protein, was shown to move processively along the microtubule for more than 1 micrometer. The movement along the microtubules was stochastic and fitted a biased Brownian-movement model. (+info)Microtubule-dependent plus- and minus end-directed motilities are competing processes for nuclear targeting of adenovirus. (2/1515)
Adenovirus (Ad) enters target cells by receptor-mediated endocytosis, escapes to the cytosol, and then delivers its DNA genome into the nucleus. Here we analyzed the trafficking of fluorophore-tagged viruses in HeLa and TC7 cells by time-lapse microscopy. Our results show that native or taxol-stabilized microtubules (MTs) support alternating minus- and plus end-directed movements of cytosolic virus with elementary speeds up to 2.6 micrometer/s. No directed movement was observed in nocodazole-treated cells. Switching between plus- and minus end-directed elementary speeds at frequencies up to 1 Hz was observed in the periphery and near the MT organizing center (MTOC) after recovery from nocodazole treatment. MT-dependent motilities allowed virus accumulation near the MTOC at population speeds of 1-10 micrometer/min, depending on the cell type. Overexpression of p50/dynamitin, which is known to affect dynein-dependent minus end-directed vesicular transport, significantly reduced the extent and the frequency of minus end-directed migration of cytosolic virus, and increased the frequency, but not the extent of plus end-directed motility. The data imply that a single cytosolic Ad particle engages with two types of MT-dependent motor activities, the minus end- directed cytoplasmic dynein and an unknown plus end- directed activity. (+info)The polar flagellar motor of Vibrio cholerae is driven by an Na+ motive force. (3/1515)
Vibrio cholerae is a highly motile bacterium which possesses a single polar flagellum as a locomotion organelle. Motility is thought to be an important factor for the virulence of V. cholerae. The genome sequencing project of this organism is in progress, and the genes that are highly homologous to the essential genes of the Na+-driven polar flagellar motor of Vibrio alginolyticus were found in the genome database of V. cholerae. The energy source of its flagellar motor was investigated. We examined the Na+ dependence and the sensitivity to the Na+ motor-specific inhibitor of the motility of the V. cholerae strains and present the evidence that the polar flagellar motor of V. cholerae is driven by an Na+ motive force. (+info)p53 and p16INK4A mutations during the progression of glomus tumor. (4/1515)
Glomus tumors are significantly rare tumors of carotid body. The great majority of these tumors are benign in character. Here we present two brothers with hereditary glomus jugulare tumor who had consanguineous parents. Radiotherapy was applied approximately 8 and 10 years ago for treatment in both cases. Eight years later, one of these cases came to our notice due to relapse. The mutation pattern of p53, p57KIP2, p16INK4A and p15NK4B genes which have roles in the cell cycle, was analyzed in tumor samples obtained from the two affected cases in the initial phase and from one of these cases at relapse. The DNA sample obtained from the case in initial diagnosis phase revealed no p53, p57KIP2, p16INK4A or p15INK4B mutation. He is still in remission phase. Despite the lack of p53, p57KIP2, p16INK4A and p15INK4B mutation at initial diagnosis the tumor DNA of the other case in relapse revealed p53 codon 243 (ATG-->ATC; met-->ile) and p16 codon 97 (GAC-->AAC; asp-->asn) missense point mutations. No loss of heterozygosity in p53 and p16INK4A was observed by microsatellite analysis of tumoral tissues in these cases. P53 and p16INK4A mutations observed in relapse phase were in conserved regions of both genes. No previous reports have been published with these mutations in glomus tumor during progression. The mutation observed in this case may due to radiotherapy. In spite of this possibility, the missense point mutations in conserved region of p53 and p16INK4A genes may indicate the role of p53 and p16INK4A in tumor progression of glomus tumors. (+info)The meningococcal PilT protein is required for induction of intimate attachment to epithelial cells following pilus-mediated adhesion. (5/1515)
The ability of Neisseria meningitidis (MC) to interact with cellular barriers is essential to its pathogenesis. With epithelial cells, this process has been modeled in two steps. The initial stage of localized adherence is mediated by bacterial pili. After this phase, MC disperse and lose piliation, thus leading to a diffuse adherence. At this stage, microvilli have disappeared, and MC interact intimately with cells and are, in places, located on pedestals of actin, thus realizing attaching and effacing (AE) lesions. The bacterial attributes responsible for these latter phenotypes remain unidentified. Considering that bacteria are nonpiliated at this stage, pili cannot be directly responsible for this effect. However, the initial phase of pilus-mediated localized adherence is required for the occurrence of diffuse adherence, loss of microvilli, and intimate attachment, because nonpiliated bacteria are not capable of such a cellular interaction. In this work, we engineered a mutation in the cytoplasmic nucleotide-binding protein PilT and showed that this mutation increased piliation and abolished the dispersal phase of bacterial clumps as well as the loss of piliation. Furthermore, no intimate attachment nor AE lesions were observed. On the other hand, PilT- MC remained adherent as piliated clumps at all times. Taken together these data demonstrate that the induction of diffuse adherence, intimate attachment, and AE lesions after pilus-mediated adhesion requires the cytoplasmic PilT protein. (+info)Differences in the ionic interaction of actin with the motor domains of nonmuscle and muscle myosin II. (6/1515)
Changes in the actin-myosin interface are thought to play an important role in microfilament-linked cellular movements. In this study, we compared the actin binding properties of the motor domain of Dictyostelium discoideum (M765) and rabbit skeletal muscle myosin subfragment-1 (S1). The Dictyostelium motor domain resembles S1(A2) (S1 carrying the A2 light chain) in its interaction with G-actin. Similar to S1(A2), none of the Dictyostelium motor domain constructs induced G-actin polymerization. The affinity of monomeric actin (G-actin) was 20-fold lower for M765 than for S1(A2) but increasing the number of positive charges in the loop 2 region of the D. discoideum motor domain (residues 613-623) resulted in equivalent affinities of G-actin for M765 and for S1. Proteolytic cleavage and cross-linking approaches were used to show that M765, like S1, interacts via the loop 2 region with filamentous actin (F-actin). For both types of myosin, F-actin prevents trypsin cleavage in the loop 2 region and F-actin segment 1-28 can be cross-linked to loop 2 residues by a carbodiimide-induced reaction. In contrast with the S1, loop residues 559-565 of D. discoideum myosin was not cross-linked to F-actin, probably due to the lower number of positive charges. These results confirm the importance of the loop 2 region of myosin for the interaction with both G-actin and F-actin, regardless of the source of myosin. The differences observed in the way in which M765 and S1 interact with actin may be linked to more general differences in the structure of the actomyosin interface of muscle and nonmuscle myosins. (+info)GMAP-210, A cis-Golgi network-associated protein, is a minus end microtubule-binding protein. (7/1515)
We report that a peripheral Golgi protein with a molecular mass of 210 kD localized at the cis-Golgi network (Rios, R.M., A.M. Tassin, C. Celati, C. Antony, M.C. Boissier, J.C. Homberg, and M. Bornens. 1994. J. Cell Biol. 125:997-1013) is a microtubule-binding protein that associates in situ with a subpopulation of stable microtubules. Interaction of this protein, now called GMAP-210, for Golgi microtubule-associated protein 210, with microtubules in vitro is direct, tight and nucleotide-independent. Biochemical analysis further suggests that GMAP-210 specifically binds to microtubule ends. The full-length cDNA encoding GMAP-210 predicts a protein of 1, 979 amino acids with a very long central coiled-coil domain. Deletion analyses in vitro show that the COOH terminus of GMAP-210 binds to microtubules whereas the NH2 terminus binds to Golgi membranes. Overexpression of GMAP-210-encoding cDNA induced a dramatic enlargement of the Golgi apparatus and perturbations in the microtubule network. These effects did not occur when a mutant lacking the COOH-terminal domain was expressed. When transfected in fusion with the green fluorescent protein, the NH2-terminal domain associated with the cis-Golgi network whereas the COOH-terminal microtubule-binding domain localized at the centrosome. Altogether these data support the view that GMAP-210 serves to link the cis-Golgi network to the minus ends of centrosome-nucleated microtubules. In addition, this interaction appears essential for ensuring the proper morphology and size of the Golgi apparatus. (+info)The proapoptotic activity of the Bcl-2 family member Bim is regulated by interaction with the dynein motor complex. (8/1515)
Bcl-2 family members that have only a single Bcl-2 homology domain, BH3, are potent inducers of apoptosis, and some appear to play a critical role in developmentally programmed cell death. We examined the regulation of the proapoptotic activity of the BH3-only protein Bim. In healthy cells, most Bim molecules were bound to LC8 cytoplasmic dynein light chain and thereby sequestered to the microtubule-associated dynein motor complex. Certain apoptotic stimuli disrupted the interaction between LC8 and the dynein motor complex. This freed Bim to translocate together with LC8 to Bcl-2 and to neutralize its antiapoptotic activity. This process did not require caspase activity and therefore constitutes an initiating event in apoptosis signaling. (+info)Molecular motor proteins are a type of protein that convert chemical energy into mechanical work at the molecular level. They play a crucial role in various cellular processes, such as cell division, muscle contraction, and intracellular transport. There are several types of molecular motor proteins, including myosin, kinesin, and dynein.
Myosin is responsible for muscle contraction and movement along actin filaments in the cytoplasm. Kinesin and dynein are involved in intracellular transport along microtubules, moving cargo such as vesicles, organelles, and mRNA to various destinations within the cell.
These motor proteins move in a stepwise fashion, with each step driven by the hydrolysis of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and inorganic phosphate (Pi). The directionality and speed of movement are determined by the structure and regulation of the motor proteins, as well as the properties of the tracks along which they move.
Kinesin is not a medical term per se, but a term from the field of cellular biology. However, understanding how kinesins work is important in the context of medical and cellular research.
Kinesins are a family of motor proteins that play a crucial role in transporting various cargoes within cells, such as vesicles, organelles, and chromosomes. They move along microtubule filaments, using the energy derived from ATP hydrolysis to generate mechanical force and motion. This process is essential for several cellular functions, including intracellular transport, mitosis, and meiosis.
In a medical context, understanding kinesin function can provide insights into various diseases and conditions related to impaired intracellular transport, such as neurodegenerative disorders (e.g., Alzheimer's disease, Parkinson's disease, and Huntington's disease) and certain genetic disorders affecting motor neurons. Research on kinesins can potentially lead to the development of novel therapeutic strategies targeting these conditions.
Myosin Type V is an molecular motor protein involved in the intracellular transport of various cargoes, including vesicles and organelles. It belongs to the family of myosins, which are actin-based motors that convert chemical energy into mechanical work through the hydrolysis of ATP.
Myosin V is characterized by its long tail domain, which allows it to form dimers or higher-order oligomers, and its head domain, which binds to actin filaments and hydrolyzes ATP to generate force and movement. The protein moves in a hand-over-hand manner along the actin filament, allowing it to transport cargoes over long distances within the cell.
Myosin V has been implicated in various cellular processes, including exocytosis, endocytosis, and organelle positioning. Mutations in the MYO5A gene, which encodes Myosin Type V, have been associated with several human genetic disorders, such as Griscelli syndrome type 1 and familial progressive arthro-ophthalmopathy.
Dyneins are a type of motor protein that play an essential role in the movement of cellular components and structures within eukaryotic cells. They are responsible for generating force and motion along microtubules, which are critical components of the cell's cytoskeleton. Dyneins are involved in various cellular processes, including intracellular transport, organelle positioning, and cell division.
There are several types of dyneins, but the two main categories are cytoplasmic dyneins and axonemal dyneins. Cytoplasmic dyneins are responsible for moving various cargoes, such as vesicles, organelles, and mRNA complexes, toward the minus-end of microtubules, which is usually located near the cell center. Axonemal dyneins, on the other hand, are found in cilia and flagella and are responsible for their movement by sliding adjacent microtubules past each other.
Dyneins consist of multiple subunits, including heavy chains, intermediate chains, light-intermediate chains, and light chains. The heavy chains contain the motor domain that binds to microtubules and hydrolyzes ATP to generate force. Dysfunction in dynein proteins has been linked to various human diseases, such as neurodevelopmental disorders, ciliopathies, and cancer.
Microtubules are hollow, cylindrical structures composed of tubulin proteins in the cytoskeleton of eukaryotic cells. They play crucial roles in various cellular processes such as maintaining cell shape, intracellular transport, and cell division (mitosis and meiosis). Microtubules are dynamic, undergoing continuous assembly and disassembly, which allows them to rapidly reorganize in response to cellular needs. They also form part of important cellular structures like centrioles, basal bodies, and cilia/flagella.
Motor neurons are specialized nerve cells in the brain and spinal cord that play a crucial role in controlling voluntary muscle movements. They transmit electrical signals from the brain to the muscles, enabling us to perform actions such as walking, talking, and swallowing. There are two types of motor neurons: upper motor neurons, which originate in the brain's motor cortex and travel down to the brainstem and spinal cord; and lower motor neurons, which extend from the brainstem and spinal cord to the muscles. Damage or degeneration of these motor neurons can lead to various neurological disorders, such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA).
Myosins are a large family of motor proteins that play a crucial role in various cellular processes, including muscle contraction and intracellular transport. They consist of heavy chains, which contain the motor domain responsible for generating force and motion, and light chains, which regulate the activity of the myosin. Based on their structural and functional differences, myosins are classified into over 35 classes, with classes II, V, and VI being the most well-studied.
Class II myosins, also known as conventional myosins, are responsible for muscle contraction in skeletal, cardiac, and smooth muscles. They form filaments called thick filaments, which interact with actin filaments to generate force and movement during muscle contraction.
Class V myosins, also known as unconventional myosins, are involved in intracellular transport and organelle positioning. They have a long tail that can bind to various cargoes, such as vesicles, mitochondria, and nuclei, and a motor domain that moves along actin filaments to transport the cargoes to their destinations.
Class VI myosins are also unconventional myosins involved in intracellular transport and organelle positioning. They have two heads connected by a coiled-coil tail, which can bind to various cargoes. Class VI myosins move along actin filaments in a unique hand-over-hand motion, allowing them to transport their cargoes efficiently.
Overall, myosins are essential for many cellular functions and have been implicated in various diseases, including cardiovascular diseases, neurological disorders, and cancer.
Evoked potentials, motor, are a category of tests used in clinical neurophysiology to measure the electrical activity generated by the nervous system in response to a stimulus that specifically activates the motor pathways. These tests can help assess the integrity and function of the motor neurons, which are responsible for controlling voluntary muscle movements.
During a motor evoked potentials test, electrodes are placed on the scalp or directly on the surface of the brain or spinal cord. A stimulus is then applied to the motor cortex or peripheral nerves, causing the muscles to contract. The resulting electrical signals are recorded and analyzed to evaluate the conduction velocity, amplitude, and latency of the motor responses.
Motor evoked potentials tests can be useful in diagnosing various neurological conditions, such as multiple sclerosis, spinal cord injuries, and motor neuron diseases. They can also help monitor the progression of these conditions and assess the effectiveness of treatments.
The motor cortex is a region in the frontal lobe of the brain that is responsible for controlling voluntary movements. It is involved in planning, initiating, and executing movements of the limbs, body, and face. The motor cortex contains neurons called Betz cells, which have large cell bodies and are responsible for transmitting signals to the spinal cord to activate muscles. Damage to the motor cortex can result in various movement disorders such as hemiplegia or paralysis on one side of the body.
Optical tweezers, also known as optical traps or laser tweezers, refer to a scientific instrument that uses highly focused laser beams to manipulate and trap microscopic particles, typically smaller than a micron in diameter. The principle behind optical tweezers is the transfer of momentum between photons (light particles) and the particle being manipulated. When a laser beam is focused through a high numerical aperture objective lens, it creates an intense gradient force that attracts and holds the particle at the focus point, allowing researchers to precisely move and apply forces to the particle in three dimensions.
Optical tweezers have become an essential tool in various fields of biology, physics, and engineering due to their ability to manipulate and measure microscopic objects with high precision and non-invasively. In the medical field, optical tweezers are used for studying cell mechanics, molecular motors, DNA manipulation, protein folding, and other biological processes at the single-molecule level. Additionally, they have potential applications in diagnostics, therapeutics, and drug development by enabling the analysis of individual cells or biomolecules with unprecedented accuracy.
Myosin Type I, also known as myosin-IA, is a type of motor protein found in non-muscle cells. It is involved in various cellular processes such as organelle transport, cell division, and maintenance of cell shape. Myosin-IA consists of a heavy chain, light chains, and a cargo-binding tail domain. The heavy chain contains the motor domain that binds to actin filaments and hydrolyzes ATP to generate force and movement along the actin filament.
Myosin-I is unique among myosins because it can move in both directions along the actin filament, whereas most other myosins can only move in one direction. Additionally, myosin-I has a high duty ratio, meaning that it spends a larger proportion of its ATP hydrolysis cycle bound to the actin filament, making it well-suited for processes requiring sustained force generation or precise positioning.
Medical Definition:
Microtubule-associated proteins (MAPs) are a diverse group of proteins that bind to microtubules, which are key components of the cytoskeleton in eukaryotic cells. MAPs play crucial roles in regulating microtubule dynamics and stability, as well as in mediating interactions between microtubules and other cellular structures. They can be classified into several categories based on their functions, including:
1. Microtubule stabilizers: These MAPs promote the assembly of microtubules and protect them from disassembly by enhancing their stability. Examples include tau proteins and MAP2.
2. Microtubule dynamics regulators: These MAPs modulate the rate of microtubule polymerization and depolymerization, allowing for dynamic reorganization of the cytoskeleton during cell division and other processes. Examples include stathmin and XMAP215.
3. Microtubule motor proteins: These MAPs use energy from ATP hydrolysis to move along microtubules, transporting various cargoes within the cell. Examples include kinesin and dynein.
4. Adapter proteins: These MAPs facilitate interactions between microtubules and other cellular structures, such as membranes, organelles, or signaling molecules. Examples include MAP4 and CLASPs.
Dysregulation of MAPs has been implicated in several diseases, including neurodegenerative disorders like Alzheimer's disease (where tau proteins form abnormal aggregates called neurofibrillary tangles) and cancer (where altered microtubule dynamics can contribute to uncontrolled cell division).
Myosin Heavy Chains are the large, essential components of myosin molecules, which are responsible for the molecular motility in muscle cells. These heavy chains have a molecular weight of approximately 200 kDa and form the motor domain of myosin, which binds to actin filaments and hydrolyzes ATP to generate force and movement during muscle contraction. There are several different types of myosin heavy chains, each with specific roles in various tissues and cellular functions. In skeletal and cardiac muscles, for example, myosin heavy chains have distinct isoforms that contribute to the contractile properties of these tissues.
In the context of medicine and healthcare, "movement" refers to the act or process of changing physical location or position. It involves the contraction and relaxation of muscles, which allows for the joints to move and the body to be in motion. Movement can also refer to the ability of a patient to move a specific body part or limb, which is assessed during physical examinations. Additionally, "movement" can describe the progression or spread of a disease within the body.
Cytoplasmic dyneins are a type of motor protein found in the cytoplasm of cells. They are responsible for transporting various cellular cargoes, such as vesicles, organelles, and mRNA, along microtubules toward the minus-end of the microtubule, which is typically located near the cell center or nucleus.
Cytoplasmic dyneins are large protein complexes composed of multiple subunits, including heavy chains, intermediate chains, light intermediate chains, and light chains. The heavy chains contain the motor domain that binds to microtubules and hydrolyzes ATP to generate force for movement. Different isoforms of cytoplasmic dyneins exist, which can transport different cargoes and have distinct functions in cells.
Dysfunction of cytoplasmic dyneins has been implicated in various human diseases, including neurodegenerative disorders such as motor neuron disease and Alzheimer's disease, as well as cancer and developmental abnormalities.
"Motor activity" is a general term used in the field of medicine and neuroscience to refer to any kind of physical movement or action that is generated by the body's motor system. The motor system includes the brain, spinal cord, nerves, and muscles that work together to produce movements such as walking, talking, reaching for an object, or even subtle actions like moving your eyes.
Motor activity can be voluntary, meaning it is initiated intentionally by the individual, or involuntary, meaning it is triggered automatically by the nervous system without conscious control. Examples of voluntary motor activity include deliberately lifting your arm or kicking a ball, while examples of involuntary motor activity include heartbeat, digestion, and reflex actions like jerking your hand away from a hot stove.
Abnormalities in motor activity can be a sign of neurological or muscular disorders, such as Parkinson's disease, cerebral palsy, or multiple sclerosis. Assessment of motor activity is often used in the diagnosis and treatment of these conditions.
Auditory outer hair cells are specialized sensory receptor cells located in the cochlea of the inner ear. They are part of the organ of Corti and play a crucial role in hearing by converting sound energy into electrical signals that can be interpreted by the brain.
Unlike the more numerous and simpler auditory inner hair cells, outer hair cells are equipped with unique actin-based molecular motors called "motile" or "piezoelectric" properties. These motors enable the outer hair cells to change their shape and length in response to electrical signals, which in turn amplifies the mechanical vibrations of the basilar membrane where they are located. This amplification increases the sensitivity and frequency selectivity of hearing, allowing us to detect and discriminate sounds over a wide range of intensities and frequencies.
Damage or loss of outer hair cells is a common cause of sensorineural hearing loss, which can result from exposure to loud noises, aging, genetics, ototoxic drugs, and other factors. Currently, there are no effective treatments to regenerate or replace damaged outer hair cells, making hearing loss an irreversible condition in most cases.
Adenosine Triphosphate (ATP) is a high-energy molecule that stores and transports energy within cells. It is the main source of energy for most cellular processes, including muscle contraction, nerve impulse transmission, and protein synthesis. ATP is composed of a base (adenine), a sugar (ribose), and three phosphate groups. The bonds between these phosphate groups contain a significant amount of energy, which can be released when the bond between the second and third phosphate group is broken, resulting in the formation of adenosine diphosphate (ADP) and inorganic phosphate. This process is known as hydrolysis and can be catalyzed by various enzymes to drive a wide range of cellular functions. ATP can also be regenerated from ADP through various metabolic pathways, such as oxidative phosphorylation or substrate-level phosphorylation, allowing for the continuous supply of energy to cells.
In the context of medical terminology, "motion" generally refers to the act or process of moving or changing position. It can also refer to the range of movement of a body part or joint. However, there is no single specific medical definition for the term "motion." The meaning may vary depending on the context in which it is used.
Actin is a type of protein that forms part of the contractile apparatus in muscle cells, and is also found in various other cell types. It is a globular protein that polymerizes to form long filaments, which are important for many cellular processes such as cell division, cell motility, and the maintenance of cell shape. In muscle cells, actin filaments interact with another type of protein called myosin to enable muscle contraction. Actins can be further divided into different subtypes, including alpha-actin, beta-actin, and gamma-actin, which have distinct functions and expression patterns in the body.
Microtubule proteins are a class of structural proteins that make up the microtubules, which are key components of the cytoskeleton in eukaryotic cells. The main microtubule protein is tubulin, which exists in two forms: alpha-tubulin and beta-tubulin. These tubulins polymerize to form heterodimers, which then assemble into protofilaments, which in turn aggregate to form hollow microtubules. Microtubules are dynamic structures that undergo continuous assembly and disassembly, and they play crucial roles in various cellular processes, including intracellular transport, cell division, and maintenance of cell shape. Other microtubule-associated proteins (MAPs) also bind to microtubules and regulate their stability, dynamics, and interactions with other cellular structures.
Myosin Type II, also known as myosin II or heavy meromyosin, is a type of motor protein involved in muscle contraction and other cellular movements. It is a hexameric protein composed of two heavy chains and four light chains. The heavy chains have a head domain that binds to actin filaments and an tail domain that forms a coiled-coil structure, allowing the formation of filaments. Myosin II uses the energy from ATP hydrolysis to move along actin filaments, generating force and causing muscle contraction or other cell movements. It plays a crucial role in various cellular processes such as cytokinesis, cell motility, and maintenance of cell shape.
Biological models, also known as physiological models or organismal models, are simplified representations of biological systems, processes, or mechanisms that are used to understand and explain the underlying principles and relationships. These models can be theoretical (conceptual or mathematical) or physical (such as anatomical models, cell cultures, or animal models). They are widely used in biomedical research to study various phenomena, including disease pathophysiology, drug action, and therapeutic interventions.
Examples of biological models include:
1. Mathematical models: These use mathematical equations and formulas to describe complex biological systems or processes, such as population dynamics, metabolic pathways, or gene regulation networks. They can help predict the behavior of these systems under different conditions and test hypotheses about their underlying mechanisms.
2. Cell cultures: These are collections of cells grown in a controlled environment, typically in a laboratory dish or flask. They can be used to study cellular processes, such as signal transduction, gene expression, or metabolism, and to test the effects of drugs or other treatments on these processes.
3. Animal models: These are living organisms, usually vertebrates like mice, rats, or non-human primates, that are used to study various aspects of human biology and disease. They can provide valuable insights into the pathophysiology of diseases, the mechanisms of drug action, and the safety and efficacy of new therapies.
4. Anatomical models: These are physical representations of biological structures or systems, such as plastic models of organs or tissues, that can be used for educational purposes or to plan surgical procedures. They can also serve as a basis for developing more sophisticated models, such as computer simulations or 3D-printed replicas.
Overall, biological models play a crucial role in advancing our understanding of biology and medicine, helping to identify new targets for therapeutic intervention, develop novel drugs and treatments, and improve human health.
Axonal transport is the controlled movement of materials and organelles within axons, which are the nerve fibers of neurons (nerve cells). This intracellular transport system is essential for maintaining the structural and functional integrity of axons, particularly in neurons with long axonal processes. There are two types of axonal transport: anterograde transport, which moves materials from the cell body toward the synaptic terminals, and retrograde transport, which transports materials from the synaptic terminals back to the cell body. Anterograde transport is typically slower than retrograde transport and can be divided into fast and slow components based on velocity. Fast anterograde transport moves vesicles containing neurotransmitters and their receptors, as well as mitochondria and other organelles, at speeds of up to 400 mm/day. Slow anterograde transport moves cytoskeletal elements, proteins, and RNA at speeds of 1-10 mm/day. Retrograde transport is primarily responsible for recycling membrane components, removing damaged organelles, and transmitting signals from the axon terminal to the cell body. Dysfunctions in axonal transport have been implicated in various neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS).
The spindle apparatus is a microtubule-based structure that plays a crucial role in the process of cell division, specifically during mitosis and meiosis. It consists of three main components:
1. The spindle poles: These are organized structures composed of microtubules and associated proteins that serve as the anchoring points for the spindle fibers. In animal cells, these poles are typically formed by centrosomes, while in plant cells, they form around nucleation sites called microtubule-organizing centers (MTOCs).
2. The spindle fibers: These are dynamic arrays of microtubules that extend between the two spindle poles. They can be categorized into three types: kinetochore fibers, which connect to the kinetochores on chromosomes; astral fibers, which radiate from the spindle poles and help position the spindle within the cell; and interpolar fibers, which lie between the two spindle poles and contribute to their separation during anaphase.
3. Regulatory proteins: Various motor proteins, such as dynein and kinesin, as well as non-motor proteins like tubulin and septins, are involved in the assembly, maintenance, and dynamics of the spindle apparatus. These proteins help to generate forces that move chromosomes, position the spindle, and ultimately segregate genetic material between two daughter cells during cell division.
The spindle apparatus is essential for ensuring accurate chromosome separation and maintaining genomic stability during cell division. Dysfunction of the spindle apparatus can lead to various abnormalities, including aneuploidy (abnormal number of chromosomes) and chromosomal instability, which have been implicated in several diseases, such as cancer and developmental disorders.
Protein transport, in the context of cellular biology, refers to the process by which proteins are actively moved from one location to another within or between cells. This is a crucial mechanism for maintaining proper cell function and regulation.
Intracellular protein transport involves the movement of proteins within a single cell. Proteins can be transported across membranes (such as the nuclear envelope, endoplasmic reticulum, Golgi apparatus, or plasma membrane) via specialized transport systems like vesicles and transport channels.
Intercellular protein transport refers to the movement of proteins from one cell to another, often facilitated by exocytosis (release of proteins in vesicles) and endocytosis (uptake of extracellular substances via membrane-bound vesicles). This is essential for communication between cells, immune response, and other physiological processes.
It's important to note that any disruption in protein transport can lead to various diseases, including neurological disorders, cancer, and metabolic conditions.
Adenosine triphosphatases (ATPases) are a group of enzymes that catalyze the conversion of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and inorganic phosphate. This reaction releases energy, which is used to drive various cellular processes such as muscle contraction, transport of ions across membranes, and synthesis of proteins and nucleic acids.
ATPases are classified into several types based on their structure, function, and mechanism of action. Some examples include:
1. P-type ATPases: These ATPases form a phosphorylated intermediate during the reaction cycle and are involved in the transport of ions across membranes, such as the sodium-potassium pump and calcium pumps.
2. F-type ATPases: These ATPases are found in mitochondria, chloroplasts, and bacteria, and are responsible for generating a proton gradient across the membrane, which is used to synthesize ATP.
3. V-type ATPases: These ATPases are found in vacuolar membranes and endomembranes, and are involved in acidification of intracellular compartments.
4. A-type ATPases: These ATPases are found in the plasma membrane and are involved in various functions such as cell signaling and ion transport.
Overall, ATPases play a crucial role in maintaining the energy balance of cells and regulating various physiological processes.
Molecular models are three-dimensional representations of molecular structures that are used in the field of molecular biology and chemistry to visualize and understand the spatial arrangement of atoms and bonds within a molecule. These models can be physical or computer-generated and allow researchers to study the shape, size, and behavior of molecules, which is crucial for understanding their function and interactions with other molecules.
Physical molecular models are often made up of balls (representing atoms) connected by rods or sticks (representing bonds). These models can be constructed manually using materials such as plastic or wooden balls and rods, or they can be created using 3D printing technology.
Computer-generated molecular models, on the other hand, are created using specialized software that allows researchers to visualize and manipulate molecular structures in three dimensions. These models can be used to simulate molecular interactions, predict molecular behavior, and design new drugs or chemicals with specific properties. Overall, molecular models play a critical role in advancing our understanding of molecular structures and their functions.
Motor protein
Eukaryote
Transport by multiple-motor proteins
Stochastic thermodynamics
Kinesin-like protein KIF11
DNA
Protein-protein interaction
Anatoly B. Kolomeisky
Kinesin
Biohybrid microswimmer
Charles C. Richardson
Moroidin
Kinesin 8
Biological computing
Unconventional myosin-Va
Cytoskeleton
Unconventional myosin-Ia
Michelle Wang
Cilium
RPGRIP1L
KIF22
Molecular biophysics
MYO1C
Chromatophore
Unconventional myosin-VI
KIF2C
Molecular propeller
Extraskeletal myxoid chondrosarcoma
Coiled-coil domain-containing protein 135
Flagellar motor switch protein
Researchers interested in Molecular Motor Proteins | Yale School of Medicine
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cell
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Science News
Dynein - Wikipedia
People - The University of Nottingham
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Physics
Switch-like Arp2/3 activation upon WASP and WIP recruitment to an apparent threshold level by multivalent linker proteins in...
Wiggly proteins guard the genome | Max-Planck-Gesellschaft
Heterotaxy Syndrome and Primary Ciliary Dyskinesia: Background, Pathophysiology, Etiology
Transport in a molecular motor system | ESAIM: Mathematical Modelling and Numerical Analysis (ESAIM: M2AN)
Molecular clutch for bacterial flagellum may offer control mechanism for nanotechnology - Foresight Institute
A ROTARY MOTOR FOR BACTERIAL GLIDING [BERG LAB] - Harvard University - Department of Molecular & Cellular Biology
Discipleship: Other Subjects for Discussion | Cru
Cells' Molecular Motor Diversity Confounds Evolution | The Institute for Creation Research
Precise or Economical? | Max-Planck-Gesellschaft
CPC Definition - B82Y SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF...
Is consciousness to be found in quantum processes in microtubules? | Page 142 | Sciforums
Carlos Bustamante | Physics
Do Cells Make Noise? | Popular Science
Alternative Fuel for String-Shaped Motors in Cells - Innovations Report
Actin12
- Actin motors such as myosin move along microfilaments through interaction with actin, and microtubule motors such as dynein and kinesin move along microtubules through interaction with tubulin. (wikipedia.org)
- Myosins are a superfamily of actin motor proteins that convert chemical energy in the form of ATP to mechanical energy, thus generating force and movement. (wikipedia.org)
- Alushin hypothesizes that cells gather information about the forces they are experiencing by "reading" these structural changes, and his lab seeks to identify the actin binding proteins that act as sensors to detect these changes. (rockefeller.edu)
- It comprises three major filament systems-actin, microtubules, and intermediate filaments-along with a host of adaptors, regulators, molecular motors, and additional structural proteins. (cshlpress.com)
- All cells of higher organisms are permeated by a cytoskeleton that essentially consists of actin filaments and small protein tubes called microtubules. (tum.de)
- For this purpose they are actively transported by molecular motors on the microtubules and actin filaments. (tum.de)
- Myosin transports its freight via the actin network, but the adapter protein also interacts with the microtubules and can redirect the transport on this network. (tum.de)
- That is why the research team used zebrafish and clawed frogs for experimental investigations in Ökten's laboratory to examine the origin and the molecular mechanisms of interaction between the microtubule network and the actin network. (tum.de)
- The scientists found out that the mouse adapter protein as well as the clawed frog adapter protein has a specific domain which enables the switching between the transport of actin and microtubules. (tum.de)
- Moreover, the experimental results showed that the environmental signals which bring about the redistribution of pigment organelles in the organism of clawed frogs are associated with a change of probability with which the individual motor proteins from the actin filaments switch to the microtubule filaments. (tum.de)
- I propose to study the role of an actin cytoskeleton-motor, myosin 1b (Myo1b), a mammalian class I myosin, in regulating the morphology of sorting endosomes. (europa.eu)
- Ultimately, I wish to unravel the molecular mechanism whereby the Myo1b-dependent recruitment of actin to endosomes regulates endosomal morphology and endocytic trafficking. (europa.eu)
Mechanisms10
- Bronchial epithelial cells are the key regulators of airway inflammation, and therefore it is crucial to clarify the cellular and molecular mechanisms that are active in these cells. (medscape.com)
- They use these animal models to study the molecular and cellular mechanisms that give rise to the specific defects. (nih.gov)
- 7. [Motor Proteins of Microtubules and Mechanisms of Synaptic Plasticity]. (nih.gov)
- Drew AP, Blair IP, Nicholson GA. Molecular genetics and mechanisms of disease in distal hereditary motor neuropathies: insights directing future genetic studies. (medlineplus.gov)
- As the underlying cellular and molecular mechanisms remain incompletely understood, our study aimed to determine whether skeletal muscle myosin and its metabolic efficiency undergo alterations during hibernation to opti. (researchgate.net)
- The dynamic exchange is known to be a function of the viscous load on the flagellum, allowing the bacterium to dynamically adapt to its local viscous environment, but the molecular mechanisms of exchange and mechanosensitivity remain to be revealed. (biorxiv.org)
- Munich-based scientists have now investigated the molecular mechanisms in the cytoskeleton necessary for this and revealed potential evolutionary paths. (tum.de)
- Here the motor proteins which move the pigments organelles are subject to different regulatory mechanisms, and there is no interaction between the different cytoskeleton networks", says Ökten. (tum.de)
- However, the molecular mechanisms that control the shape of sorting endosomes are far from being elucidated. (europa.eu)
- The aim of my project is to understand the molecular mechanisms involved in tubule formation mediated by Myo1b in sorting endosomes in mammalian cells. (europa.eu)
Biophysics4
- To understand the detailed mechanism of the myosin superfamily, we undertake a multidisciplinary approach, including techniques from molecular biology, cell biology, biophysics, biochemistry and engineering. (nih.gov)
- Researchers in biophysics and bio-mechanics have made significant advances in experimental methods, and the development of new microscopes has made higher resolution molecular- and cellular-scale measurements possible. (nae.edu)
- Dr. Zeynep Ökten from the Chair of Molecular Biophysics at the Technical University of Munich (TUM) and Erwin Frey, Professor of Statistical and Biological Physics at the Ludwig-Maximilians-Universität München - with their teams - have now for the first time identified a molecular mechanism by the example of change of color among animals which explains the communication between both network systems, and revealed potential evolutionary paths. (tum.de)
- These aims employ molecular biology, biochemistry, cell biology and biophysics methodologies in a novel approach to study the shape of sorting endosomes. (europa.eu)
Kinesin motor proteins1
- 1. Understanding how kinesin motor proteins regulate postsynaptic function in neuron. (nih.gov)
Cytoskeleton6
- Motor proteins utilizing the cytoskeleton for movement fall into two categories based on their substrate: microfilaments or microtubules. (wikipedia.org)
- In addition, they appear to be involved in activities such as cell movement (motility), stabilizing the cell's structural framework (the cytoskeleton), folding and stabilizing newly produced proteins, and repairing damaged proteins. (medlineplus.gov)
- Cells are supported by a cytoskeleton made of protein filaments that provide it with an internal structure and facilitate movement. (rockefeller.edu)
- Neurofilaments (NFs) are abundant protein polymers of the axonal cytoskeleton that determine axon caliber, which is important for neuronal function. (aps.org)
- Their method is based on the internal driving motor of the white blood cells, the so-called cytoskeleton, which enables the cells to move in the body. (mpg.de)
- Motors and cytoskeleton can influence the shape of membranes, especially of high curvature, by establishing tension on membranes. (europa.eu)
Developmental Biology1
- In 1989 I started my lab in the Department of Biology (now the Department of Molecular, Cellular, and Developmental Biology) at Yale University. (yale.edu)
Dynein5
- Dynein complexes are much larger and more complex than kinesin and myosin motors. (wikipedia.org)
- 17. Kinesin and dynein superfamily proteins and the mechanism of organelle transport. (nih.gov)
- B) lrd (left-right dynein), the protein (green) mutated by the iv mutation, is also known as DNAH11, DNAHC11, and DLP11. (medscape.com)
- When the iv mouse mutation was cloned, it was found to encode a molecular motor protein, an axonemal dynein, and was named lrd, for left-right dynein (human homolog is DNAH11/DNAHC11, Dynein heavy chain 11, axonemal). (medscape.com)
- Alpha helical coiled-coils appear in many important allosteric proteins such as the dynein molecular motor and bacteria chemotaxis transmembrane receptors. (whiterose.ac.uk)
Microtubules4
- The two globular head motor domains in heavy chains can convert the chemical energy of ATP hydrolysis into mechanical work to move along microtubules. (wikipedia.org)
- In general, kinesins with N-terminal motor domains move their cargo towards the plus ends of microtubules located at the cell periphery, while kinesins with C-terminal motor domains move cargo towards the minus ends of microtubules located at the nucleus. (wikipedia.org)
- 125:997-1013) is a microtubule-binding protein that associates in situ with a subpopulation of stable microtubules. (nih.gov)
- Interaction of this protein, now called GMAP-210, for Golgi microtubule-associated protein 210, with microtubules in vitro is direct, tight and nucleotide-independent. (nih.gov)
Microtubule12
- There are two basic types of microtubule motors: plus-end motors and minus-end motors, depending on the direction in which they "walk" along the microtubule cables within the cell. (wikipedia.org)
- Genomic representation of myosin motors: Fungi (yeast): 5 Plants (Arabidopsis): 17 Insects (Drosophila): 13 Mammals (human): 40 Chromadorea ( nematode C. elegans): 15 Kinesins are a superfamily of related motor proteins that use a microtubule track in anterograde movement. (wikipedia.org)
- Genomic representation of kinesin motors: Fungi (yeast): 6 Plants (Arabidopsis thaliana): 61 Insects (Drosophila melanogaster): 25 Mammals (human): 45 Dyneins are microtubule motors capable of a retrograde sliding movement. (wikipedia.org)
- When transfected in fusion with the green fluorescent protein, the NH2-terminal domain associated with the cis-Golgi network whereas the COOH-terminal microtubule-binding domain localized at the centrosome. (nih.gov)
- 18. Polarity of Neuronal Membrane Traffic Requires Sorting of Kinesin Motor Cargo during Entry into Dendrites by a Microtubule-Associated Septin. (nih.gov)
- A common amino acid sequence in 190-kDa microtubule-associated protein and tau for the promotion of microtubule assembly. (degruyter.com)
- Conditional lethal mutants in SPC98 and SPC97 reveal a role of the encoded proteins in microtubule organization by the SPB (Knop, 1998 and references therein). (sdbonline.org)
- In contrast, Spc110p and Spc72p are the first side-specific proteins of the SPB involved in microtubule organization. (sdbonline.org)
- NFs are also cargoes of axonal transport, propelled along microtubule tracks by molecular motors. (aps.org)
- Using these tools, we can also explain differences in processivity, the ability of the motors to walk many steps along the microtubule before dissociating. (biomembranes.nl)
- There is detailed understanding of how they move and how factors such as applied force and the presence of microtubule-associated proteins can alter this single-motor travel. (biorxiv.org)
- In order to walk, the cargo-motor complex must first attach to a microtubule. (biorxiv.org)
Kinesins2
- Kinesins have two heavy chains and two light chains per active motor. (wikipedia.org)
- Kinesins are molecular motors that transport vesicles, organelles and chromosomes in cells. (biomembranes.nl)
Motility3
- Bicaudal-D regulates fragile X mental retardation protein levels, motility, and function during neuronal morphogenesis. (degruyter.com)
- Working in cell motility necessitated learning about cytoskeletal protein dynamics and function, and I embarked on the road to becoming a cell biologist. (yale.edu)
- Our research initially focused on characterizing the cytoskeletal protein dynamics and molecular motor activity underlying growth cone motility. (yale.edu)
Mechanism5
- Studies of the mechanism responsible for splicing in the brain show that the Rbfox family of RNA binding proteins plays an essential role in NM IIB splice regulation. (nih.gov)
- I will also discuss the possible operation mechanism behind the F$_1$, along with structurally-related hexameric ATPases, also mentioning the possibility of generating hybrid molecular motors. (aps.org)
- One of our goals is to artificially control concerted functions of any protein complexes and to uncover the general mechanism of allostery. (phys.org)
- As a mechanism for transmitting the information of ligand binding to a distant site across an allosteric protein, an alternative to conformational change in the mean static structure is an induced change in the pattern of the internal dynamics of the protein. (whiterose.ac.uk)
- The overarching goal is to understand the molecular mechanism underlying bidirectional transport of cargo in cells, such as axonal transport of vesicles, and how these processes are altered in neurodegenerative disease. (biomembranes.nl)
Structural6
- The Nucleolar Integrity Group investigates molecular machines involved in critical RNA processing pathways through a multidisciplinary approach combining structural, molecular, and cellular biology. (nih.gov)
- Molecular motor protein KIF5C mediates structural plasticity and long-term memory by constraining local translation. (seattlechildrens.org)
- We propose that this novel biochemical activity implicates a catalytic role of Nsp13 in protein-RNA remodeling during genome replication beyond its duplex strand separation or structural stabilization of the RTC, yielding new insight into coronavirus proofreading. (nih.gov)
- The causative genes are at least twelve, encoding structural or regulatory proteins of the thin filament, and the clinical picture as well as the histolog. (researchgate.net)
- The results have been published in two articles of the current online edition of the science magazine Nature Structural and Molecular Biology. (mytum.de)
- To investigate these changes, his group is developing a novel approach to reconstruct and visualize deformations of the filaments at a structural level as they are pulled in opposite directions by myosin motors. (rockefeller.edu)
Biological7
- These advances are complemented, on the biological side, by our knowledge of the human genome and a greater understanding of the molecular pathology of some diseases. (nih.gov)
- We hope allosteric control over concerted functions of protein complexes will open up new avenues in industrial applications of enzymes or biological, medical and agricultural fields ," said Takahiro Kosugi an assistant professor at the National Institutes of Natural Sciences. (phys.org)
- UNSW Sydney Professor Paul Curmi, from the School of Physics, with research partners at the University of Bayreuth in Germany and Lund University in Sweden, have been awarded a $16 million ERC Synergy grant for a project that aims to build artificial molecular engines using biological materials. (edu.au)
- Prof. Curmi's newly funded project aims to build a biological molecular engine from scratch to better understand how it works. (edu.au)
- In many laboratories, laser tweezers are therefore standard equipment for studying biological processes, such as individual proteins, molecular motors, DNA or the inner life of cells," the Nobel Prize press release states. (vox.com)
- Structure, function and organization of lipids and proteins in biological membranes. (biomembranes.nl)
- Molecular motors like kinesin are critical for cellular organization and biological function including in neurons. (biorxiv.org)
Cytoskeletal3
- Proteins that are involved in or cause cell movement such as the rotary structures (flagellar motor) or the structures whose movement is directed along cytoskeletal filaments. (usda.gov)
- The Laboratory of Molecular Physiology (LMP) focuses on the understanding of cytoskeletal proteins, specifically myosins, a molecular motor that converts chemical energy (ATP) to mechanical output (work/force/displacement). (nih.gov)
- Recently we have been developing biophysical methods for measuring traction forces that growth cones exert on the underlying substrate while co-assessing cytoskeletal dynamics with fluorescently tagged proteins. (yale.edu)
Superfamily2
Flagellar motor2
- The bacterial flagellar motor (BFM) is the membrane-embedded rotary molecular motor which turns the flagellum that provides thrust to many bacterial species. (biorxiv.org)
- These membrane bound protein megastructures include the bacterial flagellar motor, the most sophisticated rotary motor known to science, and a molecular syringe that is used by bacteria to drill into our cells to help them survive in the body. (aips.net.au)
Family of proteins2
- and studying the functions of the Rbfox family of proteins. (nih.gov)
- Johns Hopkins scientists have discovered how one family of proteins repels growing nerves and keeps them properly on track during development. (hopkinsmedicine.org)
Pathways1
- She explained that AAA+ ATPases are critical for regulating numerous cellular pathways, such as DNA replication, protein degradation, membrane fusion, and ribosome assembly. (nih.gov)
Neurofilaments1
- In nerve cells, this protein helps to organize a network of molecular threads called neurofilaments that maintain the diameter of specialized extensions called axons. (medlineplus.gov)
Constituent proteins2
- Protein complexes, such as hemoglobin and molecular motors, exert concerted functions through cooperative work between the subunits (constituent proteins in the protein complex ). (phys.org)
- This large multimeric complex, composed of a few dozen constituent proteins, has emerged as a hallmark of dynamic subunit exchange. (biorxiv.org)
Genetics3
- Jonathan Bird, Ph.D., is the communicating author and a postdoctoral fellow in the NIDCD Laboratory of Molecular Genetics . (nih.gov)
- 1 Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, and. (nih.gov)
- 5 Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, and [email protected] [email protected]. (nih.gov)
Laboratory6
- 2 Laboratory of Molecular Physiology and. (nih.gov)
- 4 Laboratory of Molecular Physiology and [email protected] [email protected]. (nih.gov)
- Her laboratory subjected both types to a litany of protein unfolding challenges and then compared their performance. (nih.gov)
- The Laboratory of Molecular Cardiology, led by Dr. Robert S. Adelstein, is focused on the role of non-muscle myosin II (NM II) in development and disease. (nih.gov)
- Later, he became chief of the institute's Laboratory of Molecular Carcinogenesis, and in 2014, he was appointed head of the NIEHS Epigenetics and Stem Cell Biology Laboratory . (nih.gov)
- The research in the laboratory of Charles C. Richardson focuses on the enzymology and molecular biology of DNA replication and recombination. (nih.gov)
Synaptic3
- 3. Specific depletion of the motor protein KIF5B leads to deficits in dendritic transport, synaptic plasticity and memory. (nih.gov)
- Elevated protein synthesis in microglia causes autism-like synaptic and behavioral aberrations. (seattlechildrens.org)
- Fluorescence microscopy reveals the expression of numerous synaptic proteins at these contacts, while dual patch clamp recording detects both spontaneous and multi-quantal evoked synaptic responses similar to those observed in vivo. (ca.gov)
Myosins1
- As prototypical cellular motor proteins, most myosins convert the energy of ATP into movement. (nih.gov)
Dynamics3
- Machine Learning, Coarse grained Molecular Dynamics, Quantum Mechanics/Molecular Mechanics, Cheminformatics) as well as simulated exposure to computational drug discovery research as in Big Pharma. (uwm.edu)
- Understanding protein misfolding through machine learning and large-scale molecular dynamics simulation. (uwm.edu)
- Understanding mechanochemical process in motor proteins through electrostatic-enhanced coarse-grained molecular dynamics. (uwm.edu)
20212
- Arjun Saha , Arieh Warshel* " Simulating the Directional Translocation of the Substrate by 26S Proteasome AAA+ Motor in 26S Proteasome " Proceedings of the National Academy of Sciences of the United States of America , 2021 , 118 , e2104245118. (uwm.edu)
- Vikrant Tripathy, Arjun Saha ,* Krishnan Raghavachari,* " Electrostatically Embedded Molecules-in-Molecules Approach and its Application to Molecular Clusters " Journal of Computational Chemistry , 2021 , 42 , 719. (uwm.edu)
Characterization1
- Characterization of these proteins demonstrates that they are required for neuronal differentiation during spinal cord development by regulating pre-mRNA splicing of Numb, a signaling adaptor protein. (nih.gov)
Axonal Transport2
- 16. Regulation of Axonal Transport by Protein Kinases. (nih.gov)
- Ackerley S, James PA, Kalli A, French S, Davies KE, Talbot K. A mutation in the small heat-shock protein HSPB1 leading to distal hereditary motor neuronopathy disrupts neurofilament assembly and the axonal transport of specific cellular cargoes. (medlineplus.gov)
Convert chemical energy1
- Motor proteins can convert chemical energy into movement more efficiently than man-made internal combustion engines. (edu.au)
Characterize2
- Tania Baker, Ph.D., described her efforts to characterize specialized proteins called AAA+ ATPases, which unfold and remodel other proteins. (nih.gov)
- The NIH Nanomedicine Vision A goal of this initiative is to characterize quantitatively the molecular scale components or nanomachinery of the cell and to precisely control and manipulate these molecules and supramolecular assemblies in living cells to improve human health. (nih.gov)
Spiral Staircase1
- Alushin studies how these filaments, themselves macromolecular assemblies composed of repeating protein subunits arranged like steps in a spiral staircase, physically interface with collaborating proteins. (rockefeller.edu)
Neurons4
- Functional neuromuscular junctions formed by embryonic stem cell-derived motor neurons. (ca.gov)
- To address this challenge, we have developed a simplified culture system in which stem cell-derived motor neurons are grown together with muscle cells to facilitate the formation of functional neuromuscular connections. (ca.gov)
- In this setting we were able to measure multiple parameters of motor neuron-muscle communication, and found that activity displayed by the stem cell-derived motor neurons accurately mirrors that seen with motor neurons and muscles in the body. (ca.gov)
- Previous studies have characterized these neurons with respect to their molecular and intrinsic functional properties. (ca.gov)
Membrane1
- Meet 2002 Lasker Laureate James Rothman, whose discoveries helped elucidate the universal molecular machinery that orchestrates the budding and fusion of membrane vesicles. (laskerfoundation.org)
Mutations5
- Autosomal recessive inheritance, caused by mutations in the cartilage-derived morphogenetic protein 1 (CDMP1) gene on chromosome 20q. (theodora.com)
- Researchers have identified at least 14 HSPB1 gene mutations that cause a condition called distal hereditary motor neuropathy, type II, which is characterized by progressive weakness, primarily in the feet and legs. (medlineplus.gov)
- HSPB1 gene mutations that cause distal hereditary motor neuropathy, type II change single protein building blocks (amino acids) in heat shock protein beta-1. (medlineplus.gov)
- Mutations of small heat shock proteins and human congenital diseases. (medlineplus.gov)
- This recording system thus provides a sensitive and quantitative analytical platform for evaluating the impact of motor neuron disease mutations on motor neuron-muscle communication. (ca.gov)
Intracellular1
- Most intracellular transport is carried out by teams of molecular motors. (biomembranes.nl)
Pathway3
- Rodgers and his colleagues found that a protein called hepatocyte growth factor, which exists in a latent form in the spaces between muscle cells and tissue, can activate a critical signaling pathway in the cells by binding to their surfaces. (sciencedaily.com)
- This pathway stimulates the production of proteins important in alerting the stem cells. (sciencedaily.com)
- Sorting events that occur in endosomes are very important for cellular trafficking of proteins and membranes along the endocytic pathway. (europa.eu)
Genes4
- Three genes-MYH9, MYH10, and MYH14-encode the heavy chains of the individual NMII proteins: NMII-A, NMII-B, and NMII-C, which are composed of both heavy and light chains. (nih.gov)
- Overall, protein-coding density of bacterial genomes is with 85-90% high ( McCutcheon and Moran, 2011 ) and the correlation between genome size and the number of genes is surprisingly constant ( Touchon and Rocha, 2016 ). (frontiersin.org)
- A team led by Johns Hopkins scientists has found the first clear evidence that the process behind the human immune system's remarkable ability to recognize and respond to a million different proteins might have originated from a family of genes whose only apparent function is to jump around in genetic material. (hopkinsmedicine.org)
- There are roughly 30,000 genes in each cell, and about 12,000-15,000 of those are made into proteins. (nih.gov)
Deafness2
- A research team led by scientists at the National Institute on Deafness and Other Communication Disorders (NIDCD), part of the National Institutes of Health (NIH), has discovered that a protein essential for building key hearing structures in the inner ear also plays a critical role in maintaining them throughout life. (nih.gov)
- Myosin is necessary in the process of hearing because of its role in the growth of stereocilia so defects in myosin protein structure can lead to Usher syndrome and non-syndromic deafness. (wikipedia.org)
Ribosome assembly1
- Current work in the Stanley Lab is focused on determining how molecular machines involved in ribosome assembly, such as AAA-ATPases and endoribonucleases, are regulated. (nih.gov)
Tubulin2
- No effect on other motor proteins and tubulin. (sigmaaldrich.com)
- The S. cerevisiae gamma-tubulin, Tub4p, forms a stable complex with two other proteins, Spc98p and Spc97p, and this gamma-tubulin complex (Tub4p complex) is localized at the outer and inner plaques of the SPB. (sdbonline.org)
Genomes1
- Researchers have developed a method to identify the primary interactions between incoming viral RNA genomes and host proteins. (vanderbilt.edu)
Molecules8
- The 2016 Nobel Prize in Chemistry was won by scientists, including Nobel Laureate and UNSW Visiting Professor of Chemistry Sir Fraser Stoddart , who developed molecular machines and engines consisting of molecules that convert energy from light or fuel to movement. (edu.au)
- Our project will use life's protein molecules which are more difficult to work with but have greater potential to be scaled up and refined," Prof. Curmi said. (edu.au)
- and c ) distinct classes of molecules were influenced by MAM (i.e, neuronal differentiation, the stress and immune response, and signal transduction) and HN2 (i.e, protein synthesis and apoptosis). (nih.gov)
- Purified Tub4p complex contains one molecule of Spc98p and Spc97p, and two or more molecules of Tub4p, but no other protein. (sdbonline.org)
- They fulfill a wide variety of tasks, such as the transport of molecules, the movement of muscles, the chemical conversion of substances and even the folding of other proteins. (mytum.de)
- In order to be able to track these changes on the nanometer scale, two fluorescent dye molecules were attached at exactly defined positions in the protein and used as a molecular ruler: If one dye is illuminated, the other will more strongly light up the closer it is to the first one. (mytum.de)
- John York and colleagues have demonstrated that the protein Vip1 is a rare type of bifunctional enzyme: it can both synthesize and destroy key cellular signaling molecules. (vanderbilt.edu)
- This motor consists of molecules that combine to long chains - so-called polymers - and then convert back to single molecules again. (mpg.de)
Scientists3
- Scientists believe that myosin 15, which like other motor proteins can move around the cell, helps to build stereocilia by delivering critical component parts. (nih.gov)
- In mice, for example, scientists found an adapter protein that regulates this redirection. (tum.de)
- With their new avidin-based platform, the scientists have created a possibility to specifically address leukocytes and, with the help of a specific toxin-derived enzyme, to modulate processes which are associated with the supply of energy for the molecular processes that let them move in the body. (mpg.de)
Bacterial2
- Baker's seminal work on AAA+ ATPases has implications for understanding bacterial antibiotic resistance, human mitochondrial metabolic disorders, and human diseases associated with protein misfolding," she said. (nih.gov)
- With the help of a protein adaptor, a bacterial toxin can be applied to influence processes associated with post-trauma injury. (mpg.de)
Synthetic biology2
- The creation of artificial allosteric sites into protein complexes has the potential to reveal fundamental principles for allostery and serve as tools for synthetic biology ," said Nobuyasu Koga, a professor at the Osaka University. (phys.org)
- If building an artificial molecular engine is achieved, in future years I can envisage the engine being used in biocomputers, as a building block in synthetic biology or even in molecular medicine," Prof. Curmi said. (edu.au)
Substrate1
- We biochemically characterized the enzyme by examining its catalytic functions, nucleic acid substrate specificity, and putative protein-nucleic acid remodeling activity. (nih.gov)
Muscle fibers2
- The muscle protein myosin "motors" the contraction of muscle fibers in animals. (wikipedia.org)
- Heat shock proteins also appear to play a role in the tensing of muscle fibers (muscle contraction). (medlineplus.gov)
Cell12
- If proteins are the workforce of the cell, then protein folding enables workers to assume the shapes needed to do their jobs. (nih.gov)
- Eukaryotic ribosome biogenesis is a complex process that involves the assembly of 79 ribosomal proteins with 4 ribosomal RNAs through the concerted effort of more than 200 non-ribosomal biogenesis factors within the nucleolus of the cell. (nih.gov)
- The NIH Brain Research Through Advancing Innovative Neurotechnologies® (BRAIN) Initiative Cell Census Network (BICCN) has unveiled an atlas of cell types and an anatomical neuronal wiring diagram for the mammalian primary motor cortex, derived from detailed studies of mice, monkeys, and humans. (nih.gov)
- Heat shock proteins block signals that lead to programmed cell death. (medlineplus.gov)
- Inside every cell there are protein engines that transport molecular objects to their destination. (edu.au)
- The inspiration for these engines came from cell biology where molecular motors are needed for vital processes. (edu.au)
- Proteins are the machines of the cell. (mytum.de)
- Particularly when the cell is highly stressed by heat, poisons or lack of oxygen, production of the protein is increased to limit the damage. (mytum.de)
- Both types of filaments additionally interact with hundreds of binding partners and serve as tracks for molecular motor proteins, providing the infrastructure for organizing and shaping the cell. (rockefeller.edu)
- Dylan Burnette and colleagues have discovered that two forms of the molecular motor protein myosin have distinct roles in regulating cell shape during cell division. (vanderbilt.edu)
- We have developed a theoretical model that correlates the switching probability of an individual motor protein with the cell-wide redistribution of pigment organelles", says Frey. (tum.de)
- Nature Reviews Molecular Cell Biology. (elsevierpure.com)
Synthesis1
- Our results show that wild-type Nsp13 inhibited polymerase extension whereas the ATPase-dead mutant stimulated activity, implicating an ATP-dependent catalytic function or protein interaction of Nsp13 that modulates RNA synthesis by Nsp12/7/8 during replication. (nih.gov)
Stereocilia2
- The researchers report that healthy hearing involves two distinct forms of a molecular motor protein called myosin 15 ( MYO15A )-one form that helps build stereocilia, and a second, much longer, version of the protein that is needed to maintain stereocilia. (nih.gov)
- Unconventional myosin 15 is a molecular motor expressed in inner ear hair cells that transports protein cargos within developing mechanosensory stereocilia. (nih.gov)
Complexes9
- According to a recently published research paper, an approach has been developed to create artificial allosteric sites (where by binding an effector molecule, activity at the distal active site is regulated) in protein complexes. (phys.org)
- A research team has developed a strategy for designing artificial allosteric sites into protein complexes to regulate a concerted function of a protein complex . (phys.org)
- The research team hypothesized that allosteric sites in protein complexes can be created by restoring lost functions of the pseudo-active sites which are predicted to have been lost during evolution. (phys.org)
- Various protein complexes include subunits that have pseudo-active sites. (phys.org)
- Such studies support the idea that distinct allosteric sites can be created into protein complexes by engineering pseudo-active sites. (phys.org)
- Pseudo-active sites are widespread in nature, and their approach shows promise as a means of programming allosteric control over concerted functions of protein complexes. (phys.org)
- Our strategy enables us to create allosteric sites into various kinds of protein complexes in principle. (phys.org)
- Our next step is to create allosteric control for a variety of protein complexes by our strategy. (phys.org)
- The limited number of proteins has enabled the reconstitution of a functional replisome, a determination of the structures of functional complexes, and a visualization of active replisomes by single-molecule techniques. (nih.gov)
Peripheral2
- We report that a peripheral Golgi protein with a molecular mass of 210 kD localized at the cis-Golgi network (Rios, R.M., A.M. Tassin, C. Celati, C. Antony, M.C. Boissier, J.C. Homberg, and M. Bornens. (nih.gov)
- Dierick I, Irobi J, De Jonghe P, Timmerman V. Small heat shock proteins in inherited peripheral neuropathies. (medlineplus.gov)
Chains2
- Myosin II is an elongated protein that is formed from two heavy chains with motor heads and two light chains. (wikipedia.org)
- It plays a decisive role, for example, in the folding of simple amino acid chains to functioning proteins with a precisely defined spatial structure. (mytum.de)
Distinct1
- Fourteen distinct kinesin families are known, with some additional kinesin-like proteins that cannot be classified into these families. (wikipedia.org)
Rotary motor2
Neuron disease1
- Much progress towards this goal has been made in the area of motor neuron disease through the development of methods to direct motor neuron formation from both embryonic and induced pluripotent stem cells, including those generated from disease patients. (ca.gov)
Replication3
- SARS-CoV-2, a single-stranded, positive-sense RNA virus responsible for COVID-19, requires a set of virally encoded nonstructural proteins that compose a replication-transcription complex (RTC) to replicate its 30 kilobase genome. (nih.gov)
- The assembly of proteins, the replisome, that replicates DNA is comprised of molecular motors, switches, and multiple protein-protein contacts that coordinate the movement of the replication fork. (nih.gov)
- The economy of proteins found in the replication system of bacteriophage T7 has made possible the analysis of a replisome at the molecular level. (nih.gov)
Interaction1
- Furthermore, we demonstrated for the first time the ability of the coronavirus Nsp13 to disrupt a high-affinity nucleic acid-protein interaction, in a uni-directional manner and with a preferential displacement of streptavidin complex from biotinylated ssDNA versus ssRNA. (nih.gov)
Processes3
- As a first step, this initiative will define what is needed to precisely control cellular events at the molecular level including data collection, concept and model development, and creation of the physical tools for manipulating the processes and components in living cells. (nih.gov)
- To this end, the approach will be informed by the design principles gleaned from the molecular processes and structures found in living cells. (nih.gov)
- The so-called heat shock protein Hsp90 is of crucial importance for our cells as it supports many basic processes. (mytum.de)
Mammalian1
- Fish and amphibians also have a protein corresponding to the mammalian adapter. (tum.de)
Hydrolysis1
- Using gold nanoparticle tracking, we can detect sub-steps in the chemomechanical cycle and measure how ATP hydrolysis triggers the forward step of the motor. (biomembranes.nl)
Regulation1
- Contractile muscle myosin II proteins participate in the beating of the heart and movement of the body, while non-muscle myosin IIs play an integral role in cellular movement, shape regulation, and division. (nih.gov)