Nerve Tissue: Differentiated tissue of the central nervous system composed of NERVE CELLS, fibers, DENDRITES, and specialized supporting cells.Nerve Tissue ProteinsSciatic Nerve: A nerve which originates in the lumbar and sacral spinal cord (L4 to S3) and supplies motor and sensory innervation to the lower extremity. The sciatic nerve, which is the main continuation of the sacral plexus, is the largest nerve in the body. It has two major branches, the TIBIAL NERVE and the PERONEAL NERVE.Peripheral Nerves: The nerves outside of the brain and spinal cord, including the autonomic, cranial, and spinal nerves. Peripheral nerves contain non-neuronal cells and connective tissue as well as axons. The connective tissue layers include, from the outside to the inside, the epineurium, the perineurium, and the endoneurium.Neoplasms, Nerve Tissue: Neoplasms composed of nerve tissue. This concept does not refer to neoplasms located in the nervous system or its component nerves.Portulaca: A plant genus of the family PORTULACACEAE.Nerve Regeneration: Renewal or physiological repair of damaged nerve tissue.Optic Nerve: The 2nd cranial nerve which conveys visual information from the RETINA to the brain. The nerve carries the axons of the RETINAL GANGLION CELLS which sort at the OPTIC CHIASM and continue via the OPTIC TRACTS to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the SUPERIOR COLLICULI and the SUPRACHIASMATIC NUCLEI. Though known as the second cranial nerve, it is considered part of the CENTRAL NERVOUS SYSTEM.Organic Chemistry Phenomena: The conformation, properties, reaction processes, and the properties of the reactions of carbon compounds.PropaneOptical Imaging: The use of light interaction (scattering, absorption, and fluorescence) with biological tissue to obtain morphologically based information. It includes measuring inherent tissue optical properties such as scattering, absorption, and autofluorescence; or optical properties of exogenous targeted fluorescent molecular probes such as those used in optical MOLECULAR IMAGING, or nontargeted optical CONTRAST AGENTS.Nanofibers: Submicron-sized fibers with diameters typically between 50 and 500 nanometers. The very small dimension of these fibers can generate a high surface area to volume ratio, which makes them potential candidates for various biomedical and other applications.Schwann Cells: Neuroglial cells of the peripheral nervous system which form the insulating myelin sheaths of peripheral axons.GlyoxalMaillard Reaction: One of a group of nonenzymatic reactions in which aldehydes, ketones, or reducing sugars react with amino acids, peptides, or proteins. Food browning reactions, such as those that occur with cooking of meats, and also food deterioration reactions, resulting in decreased nutritional value and color changes, are attributed to this reaction type. The Maillard reaction is studied by scientists in the agriculture, food, nutrition, and carbohydrate chemistry fields.Tissue Scaffolds: Cell growth support structures composed of BIOCOMPATIBLE MATERIALS. They are specially designed solid support matrices for cell attachment in TISSUE ENGINEERING and GUIDED TISSUE REGENERATION uses.Connective Tissue: Tissue that supports and binds other tissues. It consists of CONNECTIVE TISSUE CELLS embedded in a large amount of EXTRACELLULAR MATRIX.Nerve Fibers: Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.Proteins: Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.Carbonic Anhydrase III: A cytosolic carbonic anhydrase isoenzyme primarily expressed in skeletal muscle (MUSCLES, SKELETAL). EC 4.2.1.-Axons: Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.Leucine: An essential branched-chain amino acid important for hemoglobin formation.Protein Biosynthesis: The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.Sarcoma, YoshidaSpinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Muscle Proteins: The protein constituents of muscle, the major ones being ACTINS and MYOSINS. More than a dozen accessory proteins exist including TROPONIN; TROPOMYOSIN; and DYSTROPHIN.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.Nerve Block: Interruption of NEURAL CONDUCTION in peripheral nerves or nerve trunks by the injection of a local anesthetic agent (e.g., LIDOCAINE; PHENOL; BOTULINUM TOXINS) to manage or treat pain.Nitrogen: An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Nerve Endings: Branch-like terminations of NERVE FIBERS, sensory or motor NEURONS. Endings of sensory neurons are the beginnings of afferent pathway to the CENTRAL NERVOUS SYSTEM. Endings of motor neurons are the terminals of axons at the muscle cells. Nerve endings which release neurotransmitters are called PRESYNAPTIC TERMINALS.Sural Nerve: A branch of the tibial nerve which supplies sensory innervation to parts of the lower leg and foot.Muscles: Contractile tissue that produces movement in animals.Median Nerve: A major nerve of the upper extremity. In humans, the fibers of the median nerve originate in the lower cervical and upper thoracic spinal cord (usually C6 to T1), travel via the brachial plexus, and supply sensory and motor innervation to parts of the forearm and hand.Facial Nerve: The 7th cranial nerve. The facial nerve has two parts, the larger motor root which may be called the facial nerve proper, and the smaller intermediate or sensory root. Together they provide efferent innervation to the muscles of facial expression and to the lacrimal and SALIVARY GLANDS, and convey afferent information for TASTE from the anterior two-thirds of the TONGUE and for TOUCH from the EXTERNAL EAR.Nerve Crush: Treatment of muscles and nerves under pressure as a result of crush injuries.Peripheral Nerve Injuries: Injuries to the PERIPHERAL NERVES.Amino Acids: Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.Tibial Nerve: The medial terminal branch of the sciatic nerve. The tibial nerve fibers originate in lumbar and sacral spinal segments (L4 to S2). They supply motor and sensory innervation to parts of the calf and foot.Ulnar Nerve: A major nerve of the upper extremity. In humans, the fibers of the ulnar nerve originate in the lower cervical and upper thoracic spinal cord (usually C7 to T1), travel via the medial cord of the brachial plexus, and supply sensory and motor innervation to parts of the hand and forearm.Blood Proteins: Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Femoral Nerve: A nerve originating in the lumbar spinal cord (usually L2 to L4) and traveling through the lumbar plexus to provide motor innervation to extensors of the thigh and sensory innervation to parts of the thigh, lower leg, and foot, and to the hip and knee joints.Glycosylation End Products, Advanced: Products derived from the nonenzymatic reaction of GLUCOSE and PROTEINS in vivo that exhibit a yellow-brown pigmentation and an ability to participate in protein-protein cross-linking. These substances are involved in biological processes relating to protein turnover and it is believed that their excessive accumulation contributes to the chronic complications of DIABETES MELLITUS.Spinal Nerves: The 31 paired peripheral nerves formed by the union of the dorsal and ventral spinal roots from each spinal cord segment. The spinal nerve plexuses and the spinal roots are also included.Muscle, Skeletal: A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.Lysine: An essential amino acid. It is often added to animal feed.Collagen: A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of SKIN; CONNECTIVE TISSUE; and the organic substance of bones (BONE AND BONES) and teeth (TOOTH).Dietary Proteins: Proteins obtained from foods. They are the main source of the ESSENTIAL AMINO ACIDS.Nerve Growth Factor: NERVE GROWTH FACTOR is the first of a series of neurotrophic factors that were found to influence the growth and differentiation of sympathetic and sensory neurons. It is comprised of alpha, beta, and gamma subunits. The beta subunit is responsible for its growth stimulating activity.Trigeminal Nerve: The 5th and largest cranial nerve. The trigeminal nerve is a mixed motor and sensory nerve. The larger sensory part forms the ophthalmic, mandibular, and maxillary nerves which carry afferents sensitive to external or internal stimuli from the skin, muscles, and joints of the face and mouth and from the teeth. Most of these fibers originate from cells of the TRIGEMINAL GANGLION and project to the TRIGEMINAL NUCLEUS of the brain stem. The smaller motor part arises from the brain stem trigeminal motor nucleus and innervates the muscles of mastication.Nerve Growth Factors: Factors which enhance the growth potentialities of sensory and sympathetic nerve cells.Swine: Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Phrenic Nerve: The motor nerve of the diaphragm. The phrenic nerve fibers originate in the cervical spinal column (mostly C4) and travel through the cervical plexus to the diaphragm.Body Weight: The mass or quantity of heaviness of an individual. It is expressed by units of pounds or kilograms.Radial Nerve: A major nerve of the upper extremity. In humans the fibers of the radial nerve originate in the lower cervical and upper thoracic spinal cord (usually C5 to T1), travel via the posterior cord of the brachial plexus, and supply motor innervation to extensor muscles of the arm and cutaneous sensory fibers to extensor regions of the arm and hand.Cranial Nerves: Twelve pairs of nerves that carry general afferent, visceral afferent, special afferent, somatic efferent, and autonomic efferent fibers.Phenylalanine: An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Spinal Nerve Roots: Paired bundles of NERVE FIBERS entering and leaving the SPINAL CORD at each segment. The dorsal and ventral nerve roots join to form the mixed segmental spinal nerves. The dorsal roots are generally afferent, formed by the central projections of the spinal (dorsal root) ganglia sensory cells, and the ventral roots are efferent, comprising the axons of spinal motor and PREGANGLIONIC AUTONOMIC FIBERS.Nerve Compression Syndromes: Mechanical compression of nerves or nerve roots from internal or external causes. These may result in a conduction block to nerve impulses (due to MYELIN SHEATH dysfunction) or axonal loss. The nerve and nerve sheath injuries may be caused by ISCHEMIA; INFLAMMATION; or a direct mechanical effect.Organ Size: The measurement of an organ in volume, mass, or heaviness.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Rats, Inbred Strains: Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.Carbon Isotopes: Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Ophthalmic Nerve: A sensory branch of the trigeminal (5th cranial) nerve. The ophthalmic nerve carries general afferents from the superficial division of the face including the eyeball, conjunctiva, upper eyelid, upper nose, nasal mucosa, and scalp.TritiumMandibular Nerve: A branch of the trigeminal (5th cranial) nerve. The mandibular nerve carries motor fibers to the muscles of mastication and sensory fibers to the teeth and gingivae, the face in the region of the mandible, and parts of the dura.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Tissue Distribution: Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.Cochlear Nerve: The cochlear part of the 8th cranial nerve (VESTIBULOCOCHLEAR NERVE). The cochlear nerve fibers originate from neurons of the SPIRAL GANGLION and project peripherally to cochlear hair cells and centrally to the cochlear nuclei (COCHLEAR NUCLEUS) of the BRAIN STEM. They mediate the sense of hearing.Splanchnic Nerves: The major nerves supplying sympathetic innervation to the abdomen. The greater, lesser, and lowest (or smallest) splanchnic nerves are formed by preganglionic fibers from the spinal cord which pass through the paravertebral ganglia and then to the celiac ganglia and plexuses. The lumbar splanchnic nerves carry fibers which pass through the lumbar paravertebral ganglia to the mesenteric and hypogastric ganglia.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Glossopharyngeal Nerve: The 9th cranial nerve. The glossopharyngeal nerve is a mixed motor and sensory nerve; it conveys somatic and autonomic efferents as well as general, special, and visceral afferents. Among the connections are motor fibers to the stylopharyngeus muscle, parasympathetic fibers to the parotid glands, general and taste afferents from the posterior third of the tongue, the nasopharynx, and the palate, and afferents from baroreceptors and CHEMORECEPTOR CELLS of the carotid sinus.Mass Spectrometry: An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.Neural Conduction: The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.Optic Nerve Injuries: Injuries to the optic nerve induced by a trauma to the face or head. These may occur with closed or penetrating injuries. Relatively minor compression of the superior aspect of orbit may also result in trauma to the optic nerve. Clinical manifestations may include visual loss, PAPILLEDEMA, and an afferent pupillary defect.Optic Nerve Diseases: Conditions which produce injury or dysfunction of the second cranial or optic nerve, which is generally considered a component of the central nervous system. Damage to optic nerve fibers may occur at or near their origin in the retina, at the optic disk, or in the nerve, optic chiasm, optic tract, or lateral geniculate nuclei. Clinical manifestations may include decreased visual acuity and contrast sensitivity, impaired color vision, and an afferent pupillary defect.Myocardium: The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.Thoracic Nerves: The twelve spinal nerves on each side of the thorax. They include eleven INTERCOSTAL NERVES and one subcostal nerve. Both sensory and motor, they supply the muscles and skin of the thoracic and abdominal walls.Nerve Fibers, Myelinated: A class of nerve fibers as defined by their structure, specifically the nerve sheath arrangement. The AXONS of the myelinated nerve fibers are completely encased in a MYELIN SHEATH. They are fibers of relatively large and varied diameters. Their NEURAL CONDUCTION rates are faster than those of the unmyelinated nerve fibers (NERVE FIBERS, UNMYELINATED). Myelinated nerve fibers are present in somatic and autonomic nerves.Proteomics: The systematic study of the complete complement of proteins (PROTEOME) of organisms.Accessory Nerve: The 11th cranial nerve which originates from NEURONS in the MEDULLA and in the CERVICAL SPINAL CORD. It has a cranial root, which joins the VAGUS NERVE (10th cranial) and sends motor fibers to the muscles of the LARYNX, and a spinal root, which sends motor fibers to the TRAPEZIUS and the sternocleidomastoid muscles.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Kinetics: The rate dynamics in chemical or physical systems.Facial Nerve Injuries: Traumatic injuries to the facial nerve. This may result in FACIAL PARALYSIS, decreased lacrimation and salivation, and loss of taste sensation in the anterior tongue. The nerve may regenerate and reform its original pattern of innervation, or regenerate aberrantly, resulting in inappropriate lacrimation in response to gustatory stimuli (e.g., "crocodile tears") and other syndromes.Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Abducens Nerve: The 6th cranial nerve which originates in the ABDUCENS NUCLEUS of the PONS and sends motor fibers to the lateral rectus muscles of the EYE. Damage to the nerve or its nucleus disrupts horizontal eye movement control.Oculomotor Nerve: The 3d cranial nerve. The oculomotor nerve sends motor fibers to the levator muscles of the eyelid and to the superior rectus, inferior rectus, and inferior oblique muscles of the eye. It also sends parasympathetic efferents (via the ciliary ganglion) to the muscles controlling pupillary constriction and accommodation. The motor fibers originate in the oculomotor nuclei of the midbrain.Aging: The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.Sympathetic Nervous System: The thoracolumbar division of the autonomic nervous system. Sympathetic preganglionic fibers originate in neurons of the intermediolateral column of the spinal cord and project to the paravertebral and prevertebral ganglia, which in turn project to target organs. The sympathetic nervous system mediates the body's response to stressful situations, i.e., the fight or flight reactions. It often acts reciprocally to the parasympathetic system.Cranial Nerve Neoplasms: Benign and malignant neoplasms that arise from one or more of the twelve cranial nerves.Facial Nerve Diseases: Diseases of the facial nerve or nuclei. Pontine disorders may affect the facial nuclei or nerve fascicle. The nerve may be involved intracranially, along its course through the petrous portion of the temporal bone, or along its extracranial course. Clinical manifestations include facial muscle weakness, loss of taste from the anterior tongue, hyperacusis, and decreased lacrimation.

FGF8 induces formation of an ectopic isthmic organizer and isthmocerebellar development via a repressive effect on Otx2 expression. (1/25163)

Beads containing recombinant FGF8 (FGF8-beads) were implanted in the prospective caudal diencephalon or midbrain of chick embryos at stages 9-12. This induced the neuroepithelium rostral and caudal to the FGF8-bead to form two ectopic, mirror-image midbrains. Furthermore, cells in direct contact with the bead formed an outgrowth that protruded laterally from the neural tube. Tissue within such lateral outgrowths developed proximally into isthmic nuclei and distally into a cerebellum-like structure. These morphogenetic effects were apparently due to FGF8-mediated changes in gene expression in the vicinity of the bead, including a repressive effect on Otx2 and an inductive effect on En1, Fgf8 and Wnt1 expression. The ectopic Fgf8 and Wnt1 expression domains formed nearly complete concentric rings around the FGF8-bead, with the Wnt1 ring outermost. These observations suggest that FGF8 induces the formation of a ring-like ectopic signaling center (organizer) in the lateral wall of the brain, similar to the one that normally encircles the neural tube at the isthmic constriction, which is located at the boundary between the prospective midbrain and hindbrain. This ectopic isthmic organizer apparently sends long-range patterning signals both rostrally and caudally, resulting in the development of the two ectopic midbrains. Interestingly, our data suggest that these inductive signals spread readily in a caudal direction, but are inhibited from spreading rostrally across diencephalic neuromere boundaries. These results provide insights into the mechanism by which FGF8 induces an ectopic organizer and suggest that a negative feedback loop between Fgf8 and Otx2 plays a key role in patterning the midbrain and anterior hindbrain.  (+info)

Deletion analysis of the Drosophila Inscuteable protein reveals domains for cortical localization and asymmetric localization. (2/25163)

The Drosophila Inscuteable protein acts as a key regulator of asymmetric cell division during the development of the nervous system [1] [2]. In neuroblasts, Inscuteable localizes into an apical cortical crescent during late interphase and most of mitosis. During mitosis, Inscuteable is required for the correct apical-basal orientation of the mitotic spindle and for the asymmetric segregation of the proteins Numb [3] [4] [5], Prospero [5] [6] [7] and Miranda [8] [9] into the basal daughter cell. When Inscuteable is ectopically expressed in epidermal cells, which normally orient their mitotic spindle parallel to the embryo surface, these cells reorient their mitotic spindle and divide perpendicularly to the surface [1]. Like the Inscuteable protein, the inscuteable RNA is asymmetrically localized [10]. We show here that inscuteable RNA localization is not required for Inscuteable protein localization. We found that a central 364 amino acid domain - the Inscuteable asymmetry domain - was necessary and sufficient for Inscuteable localization and function. Within this domain, a separate 100 amino acid region was required for asymmetric localization along the cortex, whereas a 158 amino acid region directed localization to the cell cortex. The same 158 amino acid fragment could localize asymmetrically when coexpressed with the full-length protein, however, and could bind to Inscuteable in vitro, suggesting that this domain may be involved in the self-association of Inscuteable in vivo.  (+info)

p38 mitogen-activated protein kinase can be involved in transforming growth factor beta superfamily signal transduction in Drosophila wing morphogenesis. (3/25163)

p38 mitogen-activated protein kinase (p38) has been extensively studied as a stress-responsive kinase, but its role in development remains unknown. The fruit fly, Drosophila melanogaster, has two p38 genes, D-p38a and D-p38b. To elucidate the developmental function of the Drosophila p38's, we used various genetic and pharmacological manipulations to interfere with their functions: expression of a dominant-negative form of D-p38b, expression of antisense D-p38b RNA, reduction of the D-p38 gene dosage, and treatment with the p38 inhibitor SB203580. Expression of a dominant-negative D-p38b in the wing imaginal disc caused a decapentaplegic (dpp)-like phenotype and enhanced the phenotype of a dpp mutant. Dpp is a secretory ligand belonging to the transforming growth factor beta superfamily which triggers various morphogenetic processes through interaction with the receptor Thick veins (Tkv). Inhibition of D-p38b function also caused the suppression of the wing phenotype induced by constitutively active Tkv (TkvCA). Mosaic analysis revealed that D-p38b regulates the Tkv-dependent transcription of the optomotor-blind (omb) gene in non-Dpp-producing cells, indicating that the site of D-p38b action is downstream of Tkv. Furthermore, forced expression of TkvCA induced an increase in the phosphorylated active form(s) of D-p38(s). These results demonstrate that p38, in addition to its role as a transducer of emergency stress signaling, may function to modulate Dpp signaling.  (+info)

Conserved domains and lack of evidence for polyglutamine length polymorphism in the chicken homolog of the Machado-Joseph disease gene product ataxin-3. (4/25163)

Ataxin-3 is a protein of unknown function which is mutated in Machado-Joseph disease by expansion of a genetically unstable CAG repeat encoding polyglutamine. By analysis of chicken ataxin-3 we were able to identify four conserved domains of the protein and detected widespread expression in chicken tissues. In the first such analysis in a non-primate species we found that in contrast to primates, the chicken CAG repeat is short and genetically stable.  (+info)

A processive single-headed motor: kinesin superfamily protein KIF1A. (5/25163)

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)

A concise promoter region of the heart fatty acid-binding protein gene dictates tissue-appropriate expression. (6/25163)

The heart fatty acid-binding protein (HFABP) is a member of a family of binding proteins with distinct tissue distributions and diverse roles in fatty acid metabolism, trafficking, and signaling. Other members of this family have been shown to possess concise promoter regions that direct appropriate tissue-specific expression. The basis for the specific expression of the HFABP has not been previously evaluated, and the mechanisms governing expression of metabolic genes in the heart are not completely understood. We used transient and permanent transfections in ventricular myocytes, skeletal myocytes, and nonmyocytic cells to map regulatory elements in the HFABP promoter, and audited results in transgenic mice. Appropriate tissue-specific expression in cell culture and in transgenic mice was dictated by 1.2 kb of the 5'-flanking sequence of FABP3, the HFABP gene. Comparison of orthologous murine and human genomic sequences demonstrated multiple regions of near-identity within this promoter region, including a CArG-like element close to the TATA box. Binding and transactivation studies demonstrated that this element can function as an atypical myocyte enhancer-binding factor 2 site. Interactions with adjacent sites are likely to be necessary for fully appropriate, tissue-specific, developmental and metabolic regulation.  (+info)

Induction of serotonin transporter by hypoxia in pulmonary vascular smooth muscle cells. Relationship with the mitogenic action of serotonin. (7/25163)

-The increased delivery of serotonin (5-hydroxytryptamine, 5-HT) to the lung aggravates the development of hypoxia-induced pulmonary hypertension in rats, possibly through stimulation of the proliferation of pulmonary artery smooth muscle cells (PA-SMCs). In cultured rat PA-SMCs, 5-HT (10(-8) to 10(-6) mol/L) induced DNA synthesis and potentiated the mitogenic effect of platelet-derived growth factor-BB (10 ng/mL). This effect was dependent on the 5-HT transporter (5-HTT), since it was prevented by the 5-HTT inhibitors fluoxetine (10(-6) mol/L) and paroxetine (10(-7) mol/L), but it was unaltered by ketanserin (10(-6) mol/L), a 5-HT2A receptor antagonist. In PA-SMCs exposed to hypoxia, the levels of 5-HTT mRNA (measured by competitive reverse transcriptase-polymerase chain reaction) increased by 240% within 2 hours, followed by a 3-fold increase in the uptake of [3H]5-HT at 24 hours. Cotransfection of the cells with a construct of human 5-HTT promoter-luciferase gene reporter and of pCMV-beta-galactosidase gene allowed the demonstration that exposure of cells to hypoxia produced a 5.5-fold increase in luciferase activity, with no change in beta-galactosidase activity. The increased expression of 5-HTT in hypoxic cells was associated with a greater mitogenic response to 5-HT (10(-8) to 10(-6) mol/L) in the absence as well as in the presence of platelet-derived growth factor-BB. 5-HTT expression assessed by quantitative reverse transcriptase-polymerase chain reaction and in situ hybridization in the lungs was found to predominate in the media of pulmonary artery, in which a marked increase was noted in rats that had been exposed to hypoxia for 15 days. These data show that in vitro and in vivo exposure to hypoxia induces, via a transcriptional mechanism, 5-HTT expression in PA-SMCs, and that this effect contributes to the stimulatory action of 5-HT on PA-SMC proliferation. In vivo expression of 5-HTT by PA-SMC may play a key role in serotonin-mediated pulmonary vascular remodeling.  (+info)

Functional consequences of mutations in the human alpha1A calcium channel subunit linked to familial hemiplegic migraine. (8/25163)

Mutations in alpha1A, the pore-forming subunit of P/Q-type calcium channels, are linked to several human diseases, including familial hemiplegic migraine (FHM). We introduced the four missense mutations linked to FHM into human alpha1A-2 subunits and investigated their functional consequences after expression in human embryonic kidney 293 cells. By combining single-channel and whole-cell patch-clamp recordings, we show that all four mutations affect both the biophysical properties and the density of functional channels. Mutation R192Q in the S4 segment of domain I increased the density of functional P/Q-type channels and their open probability. Mutation T666M in the pore loop of domain II decreased both the density of functional channels and their unitary conductance (from 20 to 11 pS). Mutations V714A and I1815L in the S6 segments of domains II and IV shifted the voltage range of activation toward more negative voltages, increased both the open probability and the rate of recovery from inactivation, and decreased the density of functional channels. Mutation V714A decreased the single-channel conductance to 16 pS. Strikingly, the reduction in single-channel conductance induced by mutations T666M and V714A was not observed in some patches or periods of activity, suggesting that the abnormal channel may switch on and off, perhaps depending on some unknown factor. Our data show that the FHM mutations can lead to both gain- and loss-of-function of human P/Q-type calcium channels.  (+info)

  • In sympathetic neurons, the expression of NAIP-BIR3 and hippocalcin did not provide any significant protection from cell death from the withdrawal of nerve growth factor. (
  • When overexpressed, XAIP is able to block caspases extremely well and prevents cell death of sympathetic neurons when nerve growth factors are deprived. (
  • Nerve injury -induced protein (Ninjurin)-1 is a cell adhesion molecule that is upregulated in neurons and Schwann cells after transection injury in rats . (
  • The increased Na+-dependent amino acid uptake by BDNF is followed by an enhancement of overall protein synthesis associated with the differentiation of cortical neurons. (
  • Sensory neurons (a type of nerve cell) in culture that were exposed to p53-deficient oral cancer cells sprouted projections called neurites. (
  • These microRNAs nudge sensory neurons to reduce their normal gene activity and adopt genetic characteristics of a different class of nerve cells, known as adrenergic neurons, that are usually rare in the oral cavity. (
  • To confirm that the adrenergic neurons were promoting tumors, the scientists blunted adrenergic signaling in mice-either by disabling sensory nerves or giving adrenergic-blocking drugs. (
  • Nerve injury induces changes in gene transcription in dorsal root ganglion (DRG) neurons, which may contribute to nerve injury-induced neuropathic pain. (
  • Here, we report that peripheral nerve injury increases expression of the DNA methyltransferase DNMT3a in the injured DRG neurons via the activation of the transcription factor octamer transcription factor 1. (
  • Conversely, in the absence of nerve injury, mimicking this increase reduces the Kcna2 promoter activity, diminishes Kcna2 expression, decreases Kv current, increases excitability in DRG neurons and leads to spinal cord central sensitization and neuropathic pain symptoms. (
  • We report here that the de novo methyltransferase DNMT3a, but not DNMT3b, is significantly increased in the injured DRG neurons after peripheral nerve injury. (
  • In Alzheimer's disease, nerve cells (neurons) stop functioning, lose connections with each other and ultimately die. (
  • These data are consistent with interdepot differences in fatty acid flux ensuing from differences in fatty acid binding proteins and enzymes of fat metabolism. (
  • The effect of Piracetam on rat cerebral protein metabolism in vivo and in vitro was studied. (
  • These products of cell metabolism are primarily nitrogenous substances derived from protein, especially ammonia, or possibly certain short-chain fatty acids. (
  • metabolism of carbohydrates, fats, and proteins (for example, Vitamin B12 is necessary for the conversion of methylmalonate to succinic acid, an important Krebs cycle intermediate in energy production). (
  • The three main purposes of metabolism are the conversion of food/fuel to energy to run cellular processes, the conversion of food/fuel to building blocks for proteins, lipids, nucleic acids, and some carbohydrates, and the elimination of nitrogenous wastes. (
  • Metabolism is usually divided into two categories: catabolism, the breaking down of organic matter for example, the breaking down of glucose to pyruvate, by cellular respiration, and anabolism, the building up of components of cells such as proteins and nucleic acids. (
  • Many proteins are enzymes that catalyze the chemical reactions in metabolism. (
  • Large fibers we affected in axons when morphometry was used and identical pathologies were detected in the sciatic nerves. (
  • A new material made of carbon nanotubes supports the growth of nerve fibers, bridging segregated neural explants and providing a functional re-connection. (
  • In those conditions, without any scaffolds reconstructing the space between the two explants, we observed growth of nerve fibers that extended in straight bundles in any direction, but not necessarily toward the other tissue. (
  • If we insert a small piece of the carbon sponge into the space between the two, however, we see dense growth of nerve fibers that fill the structure and intertwine with the other sample. (
  • MS is an autoimmune disease -one in which the body attacks itself-in this case the immune system attacks the tissues of the brain and spinal cord (more specifically, the myelin sheaths surrounding the nerve fibers). (
  • Doctors don't know what causes MS, just that it occurs when the protective insulation, called myelin, that coats nerve fibers is gradually destroyed, leaving behind tough scar tissue. (
  • A mature myelin sheath insulates axons and increases nerve conduction velocity while protecting nerve fibers from various stresses such as physical ones. (
  • At present, the majority of synaptic vesicle proteins has been characterized, and many have been genetically analyzed in mice, Drosophila, and Caenorhabditis elegans. (
  • Intraperitoneal immunization of mice revealed a very weak response against the S region, and a high response against yeast itself: It is proposed that increasing the amount of the antigen and reducing the number of native cell wall proteins, might lead to a yeast that is usable as a safe and cheap live oral vaccine. (
  • Results from experiments in mice revise a long-held hypothesis that certain protein scaffolds are needed for synaptic activity. (
  • In mice and flies, the Arc protein forms capsids and carries genetic information. (
  • In the study , published July 10 in The Journal of Experimental Medicine, the scientists genetically engineered mice without the protein annexin A2. (
  • The investigators found that mice without annexin A2 showed a two-fold greater leakage of dye into lung tissue compared to mice with the protein. (
  • To clarify the roles of the principal thermogenic molecule mitochondrial uncoupling protein 1 (UCP1) in the sympathetically stimulated glucose utilization, we investigated the uptake of 2-deoxyglucose (2-DG) into BAT and some other tissues of UCP1-knockout (KO) mice in vivo. (
  • NE also increased the activity of AMP-activated protein kinase (AMP kinase) in BAT of WT but not UCP1-KO mice. (
  • Schwann cell-specific BIG1 conditional knockout mice, which have been generated here, exhibit reduced myelin thickness and decreased localization of myelin protein zero in the myelin membrane, compared with their littermate controls. (
  • The amounts of Arf1 in the COPI coatomer protein subunits were comparable in the knockout mice and controls. (
  • In addition to relatively fast inhibition by ionotropic receptors, GABA can modulate many signal transduction pathways by activating metabotropic G protein coupled GABA B receptors that play critical roles in long-term modulation of synaptic transmission ( Bowery 1993 ). (
  • An example would include, for example, the generation of myelin which insulates and protects nerves. (
  • Prion protein triggers are an important factor in the signals that ensure myelin maintenance and are distinct from those that direct myelination. (
  • Prion protein and antibodies POM1 and POM3, which recognize epitopes in the terminus (around amino acids (aa) 140-152) and charged clusters of prion protein (aa95-100)were used to their roll in myelin maintenance. (
  • The result indicated that neuronal expression and regulated proteolysis of prion protein are essential for myelin maintenance. (
  • The proteolipid protein ( PLP ) gene encodes two myelin-specific protein isoforms, DM-20 and PLP, which are members of the highly conserved lipophilin family of transmembrane proteins. (
  • Mature myelin sheaths play essential roles not only in insulating axons to increase nerve conduction velocity but also in protecting them from various external stresses such as physical ones. (
  • The interaction between NAIP and hippocalcin, a neuronal calcium-sensor protein, has been observed to take place in the zinc-binding region along with other specific amino acids. (
  • PLP differs from its smaller splice isoform, DM-20, by the presence of 35 amino acids in the cytoplasmic domain near the middle of the protein. (
  • Together, these data demonstrate the ability of BDNF to stimulate glucose utilization in response to an enhanced energy demand resulting from increases in amino acid uptake and protein synthesis associated with the promotion of neuronal differentiation by BDNF. (
  • Both of these high-quality proteins are easily digested and contain nutritionally-significant amounts of all essential amino acids, arginine in particular. (
  • Proteins provide the amino acids necessary for cell repair, neurotransmitter synthesis and immune function. (
  • Proteins are made of amino acids arranged in a linear chain joined together by peptide bonds. (
  • For that, we investigated the changes of CaM, CaMKII, protein kinase C (PKC) and polymerization ratios (PRs) of NF-L, NF-M and NF-H in cerebral cortex (CC, including total cortex and some gray), spinal cord (SC) and sciatic nerve (SN) of rats treated with HD at a dosage of 1.75 or 3.50 mmol/kg for 8 weeks (five times per week). (
  • These materials could be useful for covering electrodes used for treating movement disorders like Parkinson's because they are well accepted by tissue, while the implants being used today become less effective over time because of scar tissue. (
  • Neuronal apoptosis inhibitory protein (NAIP) belongs to the family of proteins called the inhibiter of apoptosis family (IAP), these proteins are one of the key regulators of apoptosis. (
  • The semaphorins are a family of proteins that are involved in signaling. (
  • These homologous endopeptidases belong to the large family of proteins called caspases (cysteine-dependent aspartate-specific protease). (
  • In mouse skeletal muscle, EPO stimulation can activate the AKT serine/threonine kinase 1 (AKT) signaling pathway, the main positive regulator of muscle protein synthesis. (
  • We hypothesized that a single intravenous EPO injection combined with acute resistance exercise would have a synergistic effect on skeletal muscle protein synthesis via activation of the AKT pathway. (
  • 2 h after the injection, the subjects completed an acute bout of leg extension resistance exercise to stimulate skeletal muscle protein synthesis. (
  • Significant interaction effects in the phosphorylation levels of the members of the AKT signaling pathway indicated a differential activation of protein synthesis signaling in older subjects when compared to young subjects. (
  • However, EPO offered no synergistic effect on vastus lateralis mixed muscle protein synthesis rate in young or older subjects. (
  • Despite its ability to activate the AKT pathway in skeletal muscle, an acute EPO injection had no additive or synergistic effect on the exercise-induced activation of muscle protein synthesis or muscle protein synthesis signaling pathways. (
  • Helps to increase nutrient shuttling (protein synthesis). (
  • This is unexpected because in nerve growth factor withdrawal, caspase-3 and -9 are activated, causing cell death, which are the very caspases blocked by NAIP. (
  • A selected set (n=11) of cell cycle components and proliferation markers (n=2) as well as the neurofibromin protein were analyzed by immunohistochemistry on a TMA with tissue cores from 106 MPNSTs and 3 neurofibromas. (
  • In addition, Ninjurin-1 was differentially expressed in various cell types in the tissues under the investigation. (
  • The encoded protein contains a high mobility group-box DNA binding domain and participates in the regulation of cell cycle genes and cellular senescence. (
  • Other pathways associated with breast cancer type 1 susceptibility protein related signaling, or associated with cancer and cell cycle/cell survivability were also affected. (
  • Immunofluorescence studies showed that the fusion protein was detectable at the cell surface and was stably expressed at a relatively high level. (
  • The antibody will cleanly immunoprecipitate the entire dynein complex from TX-100 or NP-40 lysates (including the 530 kD heavy chain, the light intermediate chains, and the light chains) from various tissues and cultured cell lines. (
  • Scientists are not absolutely sure what causes cell death and tissue loss in the Alzheimer's brain, but plaques and tangles are prime suspects. (
  • Neuromodulator-mediated phosphorylation of specific proteins in a neurotumor hybrid cell line (NCB-20). (
  • They pass to the brain where they damage functioning nervous tissue or subvert the actions of neurotransmitters, chemical messengers that carry impulses from one brain cell to another. (
  • It mainly affects the development of nerve cell tissues. (
  • Phospholipase A 2 is another protein that works with melittin to destroy cell membranes at the sting site. (
  • Hyaluronidase (2% of venom,) helps the reaction to spread to surrounding tissue by breaking down one of the components of cell tissue. (
  • This makes IGF-1 a good protagonist at targeting tissues to spur cell to cell communication (growth) or in a more autocrine cell signaling process that facilitates cell division. (
  • Colostrum has the unique ability to support normal cell growth & tissue repair. (
  • Using mouse models of oral cancer and laboratory cell cultures, the scientists confirmed the connection between p53 and nerve density. (
  • Sodium influx through these channels is necessary for the depolarization of nerve cell membranes and subsequent propagation of impulses along the course of the nerve. (
  • The corona virus has proteins that attach to the membrane of a cell. (
  • They need to penetrate the cell, and their surface protein is the key. (
  • Laminins promote early stages of peripheral nerve myelination by assembling basement membranes (BMs) on Schwann cell surfaces, leading to activation of β1 integrins and other receptors. (
  • Activation of the mitogen-activated protein kinase (MAPK) pathway results in the transcriptional induction of cyclin D1 with activation of CDK4, phosphorylation of pRb, and continued cell cycle progression from G 1 to S ( 5 , 6 ). (
  • In principle, the method is capable of identifying any protein or RNA whose overexpression in a mutant cell line confers a selectable phenotype ( 10 ). (
  • KIFC1 ( 15 ) is expressed primarily in proliferating tissues and cell lines, and KIFC2 ( 15 , 16 ) is expressed specifically in neural tissues. (
  • Arf1 is a small guanosine triphosphate-binding protein that plays multiple roles in intracellular trafficking and related signaling, both of which are processes involved in cell morphogenesis. (
  • Other proteins have structural or mechanical functions, such as those that form the cytoskeleton, a system of scaffolding that maintains the cell shape. (
  • Proteins are also important in cell signaling, immune responses, cell adhesion, active transport across membranes, and the cell cycle. (
  • Blocking this increase prevents nerve injury-induced methylation of the voltage-dependent potassium (Kv) channel subunit Kcna2 promoter region and rescues Kcna2 expression in the injured DRG and attenuates neuropathic pain. (
  • Neurofibromatosis type 1 (NF1) is one of the most common autosomal dominant inherited disorders, and carriers are at greatly increased risk of developing malignant peripheral nerve sheath tumours (MPNST). (
  • They exposed rodents with and without the protein to a low-oxygen or normal-oxygen environment for 48 hours, injected an experimental dye and then examined their organs. (
  • TUESDAY, May 21, 2019 (American Heart Association News) -- A potentially fatal buildup of abnormal proteins in the heart and other organs is being delayed in its diagnosis and undertreated -- despite new drugs that can combat it, a new study suggests. (
  • Amyloidosis happens when abnormal proteins join and attach to organs, tissues, nerves and other places in the body, disrupting normal function. (
  • The researchers discovered that annexin A2 links with another protein called vascular endothelial cadherin (VEC) and two enzymes, endothelial-specific protein tyrosine phosphatase and Src homology phosphatase-2, that help remove the phosphates and keep the gates closed. (
  • Nerve Tissue Proteins" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (
  • Sympathetic stimulation activates glucose utilization in parallel with fatty acid oxidation and thermogenesis in brown adipose tissue (BAT) through the β-adrenergic receptors. (
  • The tau protein threads with some phosphate molecules usually bind to the microtubules, helping to stabilize them. (
  • In addition, a comprehensive analysis of current small molecules targeting these antiapoptotic BCL2-proteins (e.g. (
  • We are not sure yet whether this is a harmful effect, but it seems that molecules such as proteins and toxins can pass out of the blood while the phone is switched on and cross into the brain. (
  • Indeed, the importance of this evolutionary event is emphasized by the replacement of P 0 with PLP as the dominant integral membrane protein in the CNS of higher vertebrates ( Yoshida and Colman, 1996 ). (
  • 4. The device of claim 1 or 2 wherein said non-mineralized skeletal joint tissue is selected from the group consisting of articular cartilage, ligament, tendon, intervertebral discs, joint capsule and synovial membrane tissue. (
  • Dr. Steven Schutzer of Rutgers New Jersey Medical School analyzed spinal fluid stored from nine patients who had experienced early symptoms that turned out to be MS. Using a special high-powered technology, he uncovered a small cluster of proteins that was unique to those first attacks. (
  • Thus, the principal substrate for BAT thermogenesis is considered to be fatty acids derived from triglycerides in this tissue and also from blood lipoproteins. (
  • In addition to being an excellent fiber source (mostly insoluble, which creates bulk for stool), chia is a rich plant-based source of Omega-3 fatty acids, consists of about 20 percent protein, and contains high levels of antioxidants, calcium, magnesium and iron. (
  • Indeed, it has been reported that glucose utilization in BAT is markedly enhanced in parallel with heat production after cold exposure, sympathetic nerve stimulation, and β-adrenergic agonist administration in vivo ( 4 - 10 ). (
  • In BAT, as in white adipose tissue (WAT) and other insulin-sensitive tissues, glucose utilization is activated by insulin. (
  • It can lower blood sugar (glucose) after a meal, reduce inflammation (C-Reactive Protein) and blood pressure, and is a natural blood thinner. (