A 48-Kd protein of the outer segment of the retinal rods and a component of the phototransduction cascade. Arrestin quenches G-protein activation by binding to phosphorylated photolyzed rhodopsin. Arrestin causes experimental autoimmune uveitis when injected into laboratory animals.
A PROTEIN-SERINE-THREONINE KINASE that is found in PHOTORECEPTOR CELLS. It mediates light-dependent PHOSPHORYLATION of RHODOPSIN and plays an important role in PHOTOTRANSDUCTION.
'Eye proteins' are structural or functional proteins, such as crystallins, opsins, and collagens, located in various parts of the eye, including the cornea, lens, retina, and aqueous humor, that contribute to maintaining transparency, refractive power, phototransduction, and overall integrity of the visual system.
A heterotrimeric GTP-binding protein that mediates the light activation signal from photolyzed rhodopsin to cyclic GMP phosphodiesterase and is pivotal in the visual excitation process. Activation of rhodopsin on the outer membrane of rod and cone cells causes GTP to bind to transducin followed by dissociation of the alpha subunit-GTP complex from the beta/gamma subunits of transducin. The alpha subunit-GTP complex activates the cyclic GMP phosphodiesterase which catalyzes the hydrolysis of cyclic GMP to 5'-GMP. This leads to closure of the sodium and calcium channels and therefore hyperpolarization of the rod cells. EC 3.6.1.-.
The portion of a retinal rod cell situated between the ROD INNER SEGMENT and the RETINAL PIGMENT EPITHELIUM. It contains a stack of photosensitive disk membranes laden with RHODOPSIN.
Substances that are recognized by the immune system and induce an immune reaction.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.
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.
Specialized cells in the invertebrates that detect and transduce light. They are predominantly rhabdomeric with an array of photosensitive microvilli. Illumination depolarizes invertebrate photoreceptors by stimulating Na+ influx across the plasma membrane.
Photosensitive afferent neurons located in the peripheral retina, with their density increases radially away from the FOVEA CENTRALIS. Being much more sensitive to light than the RETINAL CONE CELLS, the rod cells are responsible for twilight vision (at scotopic intensities) as well as peripheral vision, but provide no color discrimination.
A ubiquitously expressed G-protein-coupled receptor kinase subtype that has specificity for the agonist-occupied form of BETA-ADRENERGIC RECEPTORS and a variety of other G-PROTEIN-COUPLED RECEPTORS. Although it is highly homologous to G-PROTEIN-COUPLED RECEPTOR KINASE 2, it is not considered to play an essential role in regulating myocardial contractile response.
Adjustment of the eyes under conditions of low light. The sensitivity of the eye to light is increased during dark adaptation.
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Photosensitive proteins in the membranes of PHOTORECEPTOR CELLS such as the rods and the cones. Opsins have varied light absorption properties and are members of the G-PROTEIN-COUPLED RECEPTORS family. Their ligands are VITAMIN A-based chromophores.
A c-jun amino-terminal kinase that is found predominantly within NEURONS of the BRAIN, suggesting a role in stress-induced neuronal APOPTOSIS. Several isoforms of the protein with molecular sizes of 47 kDa and 52 kDa exist due to multiple ALTERNATIVE SPLICING.
A subclass of beta-adrenergic receptors (RECEPTORS, ADRENERGIC, BETA). The adrenergic beta-2 receptors are more sensitive to EPINEPHRINE than to NOREPINEPHRINE and have a high affinity for the agonist TERBUTALINE. They are widespread, with clinically important roles in SKELETAL MUSCLE; LIVER; and vascular, bronchial, gastrointestinal, and genitourinary SMOOTH MUSCLE.
Biological action and events that support the functions of the EYE and VISION, OCULAR.
Photosensitive afferent neurons located primarily within the FOVEA CENTRALIS of the MACULA LUTEA. There are three major types of cone cells (red, blue, and green) whose photopigments have different spectral sensitivity curves. Retinal cone cells operate in daylight vision (at photopic intensities) providing color recognition and central visual acuity.
A genus of scallops in the family PECTINIDAE, class BIVALVIA. The shell is usually radially ribbed.
A subclass of myosins originally found in the photoreceptor of DROSOPHILA. The heavy chains can occur as two alternatively spliced isoforms of 132 and 174 KDa. The amino terminal of myosin type III is highly unusual in that it contains a protein kinase domain which may be an important component of the visual process.
The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.
Photosensitive proteins expressed in the ROD PHOTORECEPTOR CELLS. They are the protein components of rod photoreceptor pigments such as RHODOPSIN.
"In the context of medicine, 'History' refers to the detailed narrative account of a patient's past and present health conditions, symptoms, treatments, lifestyle, and other relevant information, obtained through interviewing the patient or their significant others."

How does arrestin respond to the phosphorylated state of rhodopsin? (1/474)

Visual arrestin quenches light-induced signaling by binding to light-activated, phosphorylated rhodopsin (P-Rh*). Here we present structure-function data, which in conjunction with the refined crystal structure of arrestin (Hirsch, J. A., Schubert, C., Gurevich, V. V., and Sigler, P. B. (1999) Cell, in press), support a model for the conversion of a basal or "inactive" conformation of free arrestin to one that can bind to and inhibit the light activated receptor. The trigger for this transition is an interaction of the phosphorylated COOH-terminal segment of the receptor with arrestin that disrupts intramolecular interactions, including a hydrogen-bonded network of buried, charged side chains, referred to as the "polar core." This disruption permits structural adjustments that allow arrestin to bind to the receptor. Our mutational survey identifies residues in arrestin (Arg175, Asp30, Asp296, Asp303, Arg382), which when altered bypass the need for the interaction with the receptor's phosphopeptide, enabling arrestin to bind to activated, nonphosphorylated rhodopsin (Rh*). These mutational changes disrupt interactions and substructures which the crystallographic model and previous biochemical studies have shown are responsible for maintaining the inactive state. The molecular basis for these disruptions was confirmed by successfully introducing structure-based second site substitutions that restored the critical interactions. The nearly absolute conservation of the mutagenically sensitive residues throughout the arrestin family suggests that this mechanism is likely to be applicable to arrestin-mediated desensitization of most G-protein-coupled receptors.  (+info)

The 2.8 A crystal structure of visual arrestin: a model for arrestin's regulation. (2/474)

G protein-coupled signaling is utilized by a wide variety of eukaryotes for communicating information from the extracellular environment. Signal termination is achieved by the action of the arrestins, which bind to activated, phosphorylated G protein-coupled receptors. We describe here crystallographic studies of visual arrestin in its basal conformation. The salient features of the structure are a bipartite molecule with an unusual polar core. This core is stabilized in part by an extended carboxy-terminal tail that locks the molecule into an inactive state. In addition, arrestin is found to be a dimer of two asymmetric molecules, suggesting an intrinsic conformational plasticity. In conjunction with biochemical and mutagenesis data, we propose a molecular mechanism by which arrestin is activated for receptor binding.  (+info)

G-protein coupled receptor kinases as modulators of G-protein signalling. (3/474)

G-protein coupled receptors (GPCRs) comprise one of the largest classes of signalling molecules. A wide diversity of activating ligands induce the active conformation of GPCRs and lead to signalling via heterotrimeric G-proteins and downstream effectors. In addition, a complex series of reactions participate in the 'turn-off' of GPCRs in both physiological and pharmacological settings. Some key players in the inactivation or 'desensitization' of GPCRs have been identified, whereas others remain the target of ongoing studies. G-protein coupled receptor kinases (GRKs) specifically phosphorylate activated GPCRs and initiate homologous desensitization. Uncoupling proteins, such as members of the arrestin family, bind to the phosphorylated and activated GPCRs and cause desensitization by precluding further interactions of the GPCRs and G-proteins. Adaptor proteins, including arrestins, and endocytic machinery participate in the internalization of GPCRs away from their normal signalling milieu. In this review we discuss the roles of these regulatory molecules as modulators of GPCR signalling.  (+info)

Immediate upstream sequence of arrestin directs rod-specific expression in Xenopus. (4/474)

Arrestins are a family of proteins that modulate G protein-coupled receptor responses with distinct arrestin genes expressed in rods and cones. To understand the regulatory mechanisms controlling rod-specific expression, the abundant Xenopus rod arrestin cDNA and a partial genomic clone, containing the immediate upstream region and amino terminus of the polypeptide, have been characterized. The deduced polypeptide has approximately 69% identity to other vertebrate rod arrestins. Southern blot analysis and polymerase chain reaction of intronic sequences demonstrated multiple alleles for rod arrestin. DNase I footprinting with retinal proteins revealed four major DNA binding sites in the proximal promoter, coinciding with consensus sequences reported in mammalian promoters. Purified bovine Crx homeodomain and mouse Nrl proteins protected a number of these sites. A dual approach of transient embryo transfections and transgenesis was used to locate transcriptional control sequences essential for rod-specific expression in Xenopus. Constructs containing -1287/+113 of 5' upstream sequence with or without intron 1 directed high level expression, specifically in rods. A construct containing only -287/+113 directed expression of green fluorescent protein solely in rod cells. These results suggest that the Crx and Nrl binding sites in the proximal promoter are the primary cis-acting sequences regulating arrestin gene expression in rods.  (+info)

Successful cotransplantation of intact sheets of fetal retina with retinal pigment epithelium. (5/474)

PURPOSE: Many retinal diseases, such as macular degeneration, affect both retinal pigment epithelium (RPE) and photoreceptors. Therefore, retinal repair may require transplantation of both tissues together as a cograft. METHODS: As recipients of retina-RPE cografts, 7- to 10-week-old albino Royal College of Surgeons rats that lose their photoreceptors because of a pigment epithelium defect were used. Freshly harvested intact sheets of RPE with neural retina from pigmented normal rat fetuses were gel embedded for protection and transplanted into the subretinal space. RESULTS: After 6 to 7 weeks, with the support of the cografted RPE sheet, transplanted photoreceptors developed fully in organized parallel layers in the subretinal space. Immunohistochemistry for rhodopsin, rod alpha-transducin, and S-antigen and peanut agglutinin labeling for cone interphotoreceptor matrix domains suggested that the photoreceptors in the graft were capable of normal function. CONCLUSIONS: Freshly harvested intact sheets of fetal RPE and retina, transplanted together into the subretinal space, can develop a normal morphology. Such transplants have the potential to benefit retinal diseases with dysfunctional RPE and photoreceptors.  (+info)

Photoreceptor function of retinal transplants implicated by light-dark shift of S-antigen and rod transducin. (6/474)

The aim was to demonstrate functional properties of transplanted histologically normal photoreceptors. Subretinal intact-sheet transplants of fetal E17-E20 rat retinas to light-damaged albino rat eyes were fixed in light or dark, 2 to 42 weeks after transplantation, and stained immunohistochemically for certain phototransduction proteins. In light adapted transplants, transducin was predominantly found in inner segments of parallel-organized photoreceptors. Transducin shifted to the outer segments with dark-adaptation. S-antigen distribution was opposite to transducin. Rhodopsin distribution did not change. The shift of signal transduction proteins correlated to the light conditions indicates that normal phototransduction processes were established in photoreceptors of transplanted retinal sheets.  (+info)

Visual arrestin activity may be regulated by self-association. (7/474)

Visual arrestin is the protein responsible for rapid quenching of G-protein-coupled receptor signaling. Arrestin exists as a latent inhibitor which must be 'activated' upon contact with a phosphorylated receptor. X-ray crystal structures of visual arrestin exhibit a tetrameric arrangement wherein an asymmetric dimer with an extensive interface between conformationally different subunits is related to a second asymmetric dimer by a local two-fold rotation axis. To test the biological relevance of this molecular organization in solution, we carried out a sedimentation equilibrium analysis of arrestin at both crystallographic and physiological protein concentrations. While the tetrameric form can exist at the high concentrations used in crystallography experiments, we find that arrestin participates in a monomer/dimer equilibrium at concentrations more likely to be physiologically relevant. Solution interaction analysis of a proteolytically modified, constitutively active form of arrestin shows diminished dimerization. We propose that self-association of arrestin may provide a mechanism for regulation of arrestin activity by (i) ensuring an adequate supply for rapid quenching of the visual signal and (ii) limiting the availability of active monomeric species, thereby preventing inappropriate signal termination.  (+info)

Differential expression of nitric oxide synthase in experimental uveoretinitis. (8/474)

PURPOSE: To investigate the site and the cellular source of inducible nitric oxide synthase (iNOS) expression in human S-antigen peptide-induced experimental autoimmune uveoretinitis (EAU). METHODS: Twenty-one Lewis rats were sensitized with human S-antigen peptides. Three rats were killed each consecutive day from day 6 through day 12 after sensitization. Frozen sections of the enucleated eyes were analyzed for iNOS by the dual immunohistochemical method. Primary antibodies included rabbit anti-mouse iNOS combined with anti-human endothelium NOS, anti-rat lysosomal protein (ED1), or anti-rat major histocompatibility complex class II molecule (OX6) monoclonal antibodies. Secondary antibodies were fluorescein-conjugated anti-mouse IgG and streptavidin rhodamine-labeled anti-rabbit IgG. The adjacent sections were separately stained with ED1, iNOS, and glial fibrillary acidic protein (GFAP). The mouse macrophage cell line RAW 264.7 was exposed to either interferon (IFN)gamma/lipopolysaccharide (LPS) or S-antigen and to interphotoreceptor retinoid-binding protein (IRBP), myelin basic protein, and bovine serum albumin for 12 hours. Cells were harvested for detection of iNOS expression by northern blot analysis hybridization and detection of protein by immunohistochemistry. RESULTS: In the retina of eyes with EAU, ED1+/iNOS+ and OX6+/iNOS+ cells were first detected on day 9 after sensitization. These iNOS+ cells increased in number on subsequent days in parallel with the increasing severity of retinal damage. Most of the cells localized around the outer retina. In contrast, a large number of ED1+ and OX6+ cells that were localized in the uvea and conjunctiva were negative for iNOS. Retinal pigment epithelial cells did not stain for iNOS. Macrophages exposed to IFNgamma/LPS, S-antigen, and IRBP showed expression of iNOS mRNA and the protein. CONCLUSIONS: Macrophages are an important source of NO production in eyes with EAU. These macrophages preferentially express iNOS in the retina. Such a differential expression of iNOS by the macrophages appears to be related to retinal soluble proteins.  (+info)

Arrestin is a type of protein that plays a crucial role in regulating the signaling of G protein-coupled receptors (GPCRs) in cells. These receptors are involved in various cellular responses to hormones, neurotransmitters, and other signaling molecules.

When a signaling molecule binds to a GPCR, it activates the receptor and triggers a cascade of intracellular events, including the activation of G proteins. Arrestin binds to the activated GPCR and prevents further interaction with G proteins, effectively turning off the signal.

There are two main types of arrestins: visual arrestin (or rod arrestin) and non-visual arrestins (which include β-arrestin1 and β-arrestin2). Visual arrestin is primarily found in the retina and plays a role in regulating the light-sensitive proteins rhodopsin and cone opsin. Non-visual arrestins, on the other hand, are expressed throughout the body and regulate various GPCRs involved in diverse physiological processes such as cell growth, differentiation, and migration.

By modulating GPCR signaling, arrestins help maintain proper cellular function and prevent overactivation of signaling pathways that could lead to disease. Dysregulation of arrestin function has been implicated in various pathologies, including cancer, cardiovascular diseases, and neurological disorders.

G-Protein-Coupled Receptor Kinase 1 (GRK1) is a serine/threonine kinase that specifically phosphorylates and desensitizes G-protein-coupled receptors (GPCRs) upon agonist activation. GRK1 plays a crucial role in the regulation of GPCR signaling, which is involved in various physiological processes, including sensory perception, neurotransmission, and hormonal regulation.

GRK1 is primarily expressed in the retina and testis, where it regulates the activity of rhodopsin and β-adrenergic receptors, respectively. The kinase activity of GRK1 leads to the recruitment of arrestin proteins, which uncouple the receptor from its G protein, thereby terminating the signaling response. Additionally, GRK1-mediated phosphorylation creates binding sites for β-arrestins, leading to receptor internalization and subsequent degradation or recycling.

Mutations in GRK1 have been associated with various diseases, including retinitis pigmentosa, a genetic disorder that causes progressive vision loss. Therefore, understanding the function and regulation of GRK1 is essential for developing therapeutic strategies targeting GPCR-mediated diseases.

Eye proteins, also known as ocular proteins, are specific proteins that are found within the eye and play crucial roles in maintaining proper eye function and health. These proteins can be found in various parts of the eye, including the cornea, iris, lens, retina, and other structures. They perform a wide range of functions, such as:

1. Structural support: Proteins like collagen and elastin provide strength and flexibility to the eye's tissues, enabling them to maintain their shape and withstand mechanical stress.
2. Light absorption and transmission: Proteins like opsins and crystallins are involved in capturing and transmitting light signals within the eye, which is essential for vision.
3. Protection against damage: Some eye proteins, such as antioxidant enzymes and heat shock proteins, help protect the eye from oxidative stress, UV radiation, and other environmental factors that can cause damage.
4. Regulation of eye growth and development: Various growth factors and signaling molecules, which are protein-based, contribute to the proper growth, differentiation, and maintenance of eye tissues during embryonic development and throughout adulthood.
5. Immune defense: Proteins involved in the immune response, such as complement components and immunoglobulins, help protect the eye from infection and inflammation.
6. Maintenance of transparency: Crystallin proteins in the lens maintain its transparency, allowing light to pass through unobstructed for clear vision.
7. Neuroprotection: Certain eye proteins, like brain-derived neurotrophic factor (BDNF), support the survival and function of neurons within the retina, helping to preserve vision.

Dysfunction or damage to these eye proteins can contribute to various eye disorders and diseases, such as cataracts, age-related macular degeneration, glaucoma, diabetic retinopathy, and others.

Transducin is a G protein found in the rod cells of the retina and plays a crucial role in the visual signal transduction pathway. It is responsible for converting the light-induced isomerization of rhodopsin into a biochemical signal, which ultimately leads to the activation of downstream effectors and the generation of a neural response.

Transducin has three subunits: alpha (Tα), beta (Tβ), and gamma (Tγ). When light activates rhodopsin, it interacts with the Tα subunit, causing it to exchange GDP for GTP and dissociate from the Tβγ complex. The activated Tα then interacts with a downstream effector called phosphodiesterase (PDE), which leads to the hydrolysis of cGMP and the closure of cGMP-gated ion channels in the plasma membrane. This results in the hyperpolarization of the rod cell, which is the initial step in the visual signal transduction pathway.

Overall, transducin is a key player in the conversion of light energy into neural signals, allowing us to see and perceive our visual world.

A rod cell outer segment is a specialized structure in the retina of the eye that is responsible for photoreception, or the conversion of light into electrical signals. Rod cells are one of the two types of photoreceptor cells in the retina, with the other type being cone cells. Rod cells are more sensitive to light than cone cells and are responsible for low-light vision and peripheral vision.

The outer segment of a rod cell is a long, thin structure that contains stacks of discs filled with the visual pigment rhodopsin. When light hits the rhodopsin molecules in the discs, it causes a chemical reaction that leads to the activation of a signaling pathway within the rod cell. This ultimately results in the generation of an electrical signal that is transmitted to the brain via the optic nerve.

The outer segment of a rod cell is constantly being regenerated and broken down through a process called shedding and renewal. The tips of the outer segments are shed and phagocytosed by cells called retinal pigment epithelial (RPE) cells, which help to maintain the health and function of the rod cells.

An antigen is a substance (usually a protein) that is recognized as foreign by the immune system and stimulates an immune response, leading to the production of antibodies or activation of T-cells. Antigens can be derived from various sources, including bacteria, viruses, fungi, parasites, and tumor cells. They can also come from non-living substances such as pollen, dust mites, or chemicals.

Antigens contain epitopes, which are specific regions on the antigen molecule that are recognized by the immune system. The immune system's response to an antigen depends on several factors, including the type of antigen, its size, and its location in the body.

In general, antigens can be classified into two main categories:

1. T-dependent antigens: These require the help of T-cells to stimulate an immune response. They are typically larger, more complex molecules that contain multiple epitopes capable of binding to both MHC class II molecules on antigen-presenting cells and T-cell receptors on CD4+ T-cells.
2. T-independent antigens: These do not require the help of T-cells to stimulate an immune response. They are usually smaller, simpler molecules that contain repetitive epitopes capable of cross-linking B-cell receptors and activating them directly.

Understanding antigens and their properties is crucial for developing vaccines, diagnostic tests, and immunotherapies.

In the context of medical terminology, "light" doesn't have a specific or standardized definition on its own. However, it can be used in various medical terms and phrases. For example, it could refer to:

1. Visible light: The range of electromagnetic radiation that can be detected by the human eye, typically between wavelengths of 400-700 nanometers. This is relevant in fields such as ophthalmology and optometry.
2. Therapeutic use of light: In some therapies, light is used to treat certain conditions. An example is phototherapy, which uses various wavelengths of ultraviolet (UV) or visible light for conditions like newborn jaundice, skin disorders, or seasonal affective disorder.
3. Light anesthesia: A state of reduced consciousness in which the patient remains responsive to verbal commands and physical stimulation. This is different from general anesthesia where the patient is completely unconscious.
4. Pain relief using light: Certain devices like transcutaneous electrical nerve stimulation (TENS) units have a 'light' setting, indicating lower intensity or frequency of electrical impulses used for pain management.

Without more context, it's hard to provide a precise medical definition of 'light'.

Ocular vision refers to the ability to process and interpret visual information that is received by the eyes. This includes the ability to see clearly and make sense of the shapes, colors, and movements of objects in the environment. The ocular system, which includes the eye and related structures such as the optic nerve and visual cortex of the brain, works together to enable vision.

There are several components of ocular vision, including:

* Visual acuity: the clarity or sharpness of vision
* Field of vision: the extent of the visual world that is visible at any given moment
* Color vision: the ability to distinguish different colors
* Depth perception: the ability to judge the distance of objects in three-dimensional space
* Contrast sensitivity: the ability to distinguish an object from its background based on differences in contrast

Disorders of ocular vision can include refractive errors such as nearsightedness or farsightedness, as well as more serious conditions such as cataracts, glaucoma, and macular degeneration. These conditions can affect one or more aspects of ocular vision and may require medical treatment to prevent further vision loss.

"Cattle" is a term used in the agricultural and veterinary fields to refer to domesticated animals of the genus *Bos*, primarily *Bos taurus* (European cattle) and *Bos indicus* (Zebu). These animals are often raised for meat, milk, leather, and labor. They are also known as bovines or cows (for females), bulls (intact males), and steers/bullocks (castrated males). However, in a strict medical definition, "cattle" does not apply to humans or other animals.

Photoreceptor cells in invertebrates are specialized sensory neurons that convert light stimuli into electrical signals. These cells are primarily responsible for the ability of many invertebrates to detect and respond to light, enabling behaviors such as phototaxis (movement towards or away from light) and vision.

Invertebrate photoreceptor cells typically contain light-sensitive pigments that absorb light at specific wavelengths. The most common type of photopigment is rhodopsin, which consists of a protein called opsin and a chromophore called retinal. When light hits the photopigment, it changes the conformation of the chromophore, triggering a cascade of molecular events that ultimately leads to the generation of an electrical signal.

Invertebrate photoreceptor cells can be found in various locations throughout the body, depending on their function. For example, simple eyespots containing a few photoreceptor cells may be scattered over the surface of the body in some species, while more complex eyes with hundreds or thousands of photoreceptors may be present in other groups. In addition to their role in vision, photoreceptor cells can also serve as sensory organs for regulating circadian rhythms, detecting changes in light intensity, and mediating social behaviors.

Retinal rod photoreceptor cells are specialized neurons in the retina of the eye that are primarily responsible for vision in low light conditions. They contain a light-sensitive pigment called rhodopsin, which undergoes a chemical change when struck by a single photon of light. This triggers a cascade of biochemical reactions that ultimately leads to the generation of electrical signals, which are then transmitted to the brain via the optic nerve.

Rod cells do not provide color vision or fine detail, but they allow us to detect motion and see in dim light. They are more sensitive to light than cone cells, which are responsible for color vision and detailed sight in bright light conditions. Rod cells are concentrated at the outer edges of the retina, forming a crescent-shaped region called the peripheral retina, with fewer rod cells located in the central region of the retina known as the fovea.

G-Protein-Coupled Receptor Kinase 3 (GRK3) is a type of enzyme belonging to the GRK family, which plays a crucial role in the regulation of G protein-coupled receptors (GPCRs). These receptors are involved in various cellular responses and signaling pathways.

GRK3 specifically phosphorylates agonist-activated GPCRs, leading to their desensitization and internalization. This process helps maintain the balance of GPCR signaling and prevents overstimulation of downstream effectors. Mutations in GRK3 have been implicated in several diseases, including cancer, heart disease, and mental disorders.

In summary, GRK3 is a key regulator of GPCR function, modulating their activity through phosphorylation-mediated desensitization and internalization.

Dark adaptation is the process by which the eyes adjust to low levels of light. This process allows the eyes to become more sensitive to light and see better in the dark. It involves the dilation of the pupils, as well as chemical changes in the rods and cones (photoreceptor cells) of the retina. These changes allow the eye to detect even small amounts of light and improve visual acuity in low-light conditions. Dark adaptation typically takes several minutes to occur fully, but can be faster or slower depending on various factors such as age, prior exposure to light, and certain medical conditions. It is an important process for maintaining good vision in a variety of lighting conditions.

Phosphorylation is the process of adding a phosphate group (a molecule consisting of one phosphorus atom and four oxygen atoms) to a protein or other organic molecule, which is usually done by enzymes called kinases. This post-translational modification can change the function, localization, or activity of the target molecule, playing a crucial role in various cellular processes such as signal transduction, metabolism, and regulation of gene expression. Phosphorylation is reversible, and the removal of the phosphate group is facilitated by enzymes called phosphatases.

Protein binding, in the context of medical and biological sciences, refers to the interaction between a protein and another molecule (known as the ligand) that results in a stable complex. This process is often reversible and can be influenced by various factors such as pH, temperature, and concentration of the involved molecules.

In clinical chemistry, protein binding is particularly important when it comes to drugs, as many of them bind to proteins (especially albumin) in the bloodstream. The degree of protein binding can affect a drug's distribution, metabolism, and excretion, which in turn influence its therapeutic effectiveness and potential side effects.

Protein-bound drugs may be less available for interaction with their target tissues, as only the unbound or "free" fraction of the drug is active. Therefore, understanding protein binding can help optimize dosing regimens and minimize adverse reactions.

Opsins are a type of protein that are sensitive to light and play a crucial role in vision. They are found in the photoreceptor cells of the retina, which are the specialized cells in the eye that detect light. Opsins are activated by light, which triggers a series of chemical reactions that ultimately result in the transmission of a signal to the brain, allowing us to see.

There are several different types of opsins, including rhodopsin and the cone pigments, which are found in the rods and cones of the retina, respectively. Rhodopsin is responsible for dim-light vision, while the cone pigments are involved in color vision and bright-light vision.

Opsins belong to a larger family of proteins called G protein-coupled receptors (GPCRs), which are involved in many different physiological processes in the body. In addition to their role in vision, opsins have also been found to be involved in other light-dependent processes, such as the regulation of circadian rhythms and the entrainment of the biological clock.

Mitogen-Activated Protein Kinase 10 (MAPK10), also known as c-Jun N-terminal kinase 3 (JNK3), is a serine/threonine protein kinase that plays a crucial role in signal transduction pathways involved in various cellular processes, including inflammation, differentiation, and apoptosis. It is primarily expressed in the brain and testis. MAPK10 is activated by upstream MAPKKs (MKK4/MKK7) in response to stress signals or cytokines, which then phosphorylates and activates various transcription factors, such as c-Jun, thereby regulating gene expression. Dysregulation of the MAPK10 pathway has been implicated in several neurological disorders and cancers.

Adrenergic receptors are a type of G protein-coupled receptor that bind and respond to catecholamines, such as epinephrine (adrenaline) and norepinephrine (noradrenaline). Beta-2 adrenergic receptors (β2-ARs) are a subtype of adrenergic receptors that are widely distributed throughout the body, particularly in the lungs, heart, blood vessels, gastrointestinal tract, and skeletal muscle.

When β2-ARs are activated by catecholamines, they trigger a range of physiological responses, including relaxation of smooth muscle, increased heart rate and contractility, bronchodilation, and inhibition of insulin secretion. These effects are mediated through the activation of intracellular signaling pathways involving G proteins and second messengers such as cyclic AMP (cAMP).

β2-ARs have been a major focus of drug development for various medical conditions, including asthma, chronic obstructive pulmonary disease (COPD), heart failure, hypertension, and anxiety disorders. Agonists of β2-ARs, such as albuterol and salmeterol, are commonly used to treat asthma and COPD by relaxing bronchial smooth muscle and reducing airway obstruction. Antagonists of β2-ARs, such as propranolol, are used to treat hypertension, angina, and heart failure by blocking the effects of catecholamines on the heart and blood vessels.

Ocular physiological processes refer to the various functional activities and mechanisms that occur within the eye, which are essential for proper vision and eye health. These processes include:

1. Aqueous Humor Dynamics: The production, circulation, and drainage of a clear fluid called aqueous humor inside the eye, maintaining intraocular pressure.
2. Refraction and Accommodation: The bending of light rays as they pass through the cornea and lens to focus on the retina, along with the ability of the lens to change shape for near and far vision (accommodation).
3. Retinal Processing: The conversion of light energy into electrical signals by photoreceptor cells (rods and cones) in the retina, followed by signal processing and transmission through retinal ganglion cells to the optic nerve.
4. Optic Nerve Transmission: The transmission of visual information from the retina to the brain via the optic nerve, where it is further processed and interpreted as visual perception.
5. Pupillary Light Reflex: The automatic adjustment of pupil size in response to changes in light intensity, allowing for optimal light entry into the eye.
6. Extraocular Muscle Function: The coordinated movement of six extrinsic muscles that control eyeball rotation and alignment, ensuring proper fixation and tracking of visual targets.
7. Lacrimal System Function: The production, distribution, and drainage of tears to keep the ocular surface lubricated and protected from external irritants.
8. Blink Reflex and Tear Film Maintenance: The regular blinking that distributes tear film over the eye surface, protecting it from drying out and maintaining its optical clarity.
9. Circadian Rhythm Regulation: The internal regulation of sleep-wake cycles, hormonal release, and other physiological processes in response to light exposure.

Understanding ocular physiological processes is crucial for diagnosing and treating various eye conditions and diseases, as well as for developing new therapies and treatments to improve vision and overall eye health.

Retinal cone photoreceptor cells are specialized neurons located in the retina of the eye, responsible for visual phototransduction and color vision. They are one of the two types of photoreceptors, with the other being rods, which are more sensitive to low light levels. Cones are primarily responsible for high-acuity, color vision during daylight or bright-light conditions.

There are three types of cone cells, each containing different photopigments that absorb light at distinct wavelengths: short (S), medium (M), and long (L) wavelengths, which correspond to blue, green, and red light, respectively. The combination of signals from these three types of cones allows the human visual system to perceive a wide range of colors and discriminate between them. Cones are densely packed in the central region of the retina, known as the fovea, which provides the highest visual acuity.

"Pecten" is a term that has different meanings in various medical contexts. Here are two common uses:

1. In ophthalmology, the pecten is a vascular structure located on the inner surface of the eye's vitreous humor. It appears as a comb-like structure radiating from the optic disc and is more prominent in some species than others. Its function is not entirely clear, but it may play a role in nourishing the retina or helping to maintain the transparency of the vitreous humor.
2. In anatomy, "pecten" can refer to a small projection or process found on various bones, such as the pecten of the pubis (a ridge-like structure on the superior ramus of the pubic bone) or the pecten of the tongue (small projections on the underside of the tongue).

It's important to note that "pecten" is a general term with various applications, and its meaning may differ depending on the medical context.

Myosin III is a type of molecular motor protein found in cells, responsible for providing cellular movement and organization. More specifically, Myosin III is involved in the regulation of actin filament dynamics and contributes to various cellular functions such as vesicle transport, maintenance of cell shape, and signal transduction.

Myosin III has a unique motor domain that allows it to move along actin filaments while generating force. It also contains a protein kinase domain, which enables it to phosphorylate target proteins and regulate their activity. Mutations in the MYO3 gene have been associated with certain inherited diseases, such as Usher syndrome type 1F, a condition characterized by hearing loss and retinitis pigmentosa, leading to vision loss.

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.

Rhodopsin, also known as visual purple, is a light-sensitive protein found in the rods of the eye's retina. It is a type of opsin, a class of proteins that are activated by light and play a crucial role in vision. Rhodopsin is composed of two parts: an apoprotein called opsin and a chromophore called 11-cis-retinal. When light hits the retina, it changes the shape of the 11-cis-retinal, which in turn activates the rhodopsin protein. This activation triggers a series of chemical reactions that ultimately lead to the transmission of a visual signal to the brain. Rhodopsin is highly sensitive to light and allows for vision in low-light conditions.

In the context of medical terminology, "history" refers to the detailed narrative of the patient's symptoms, illnesses, treatments, and other related information gathered during a medical consultation or examination. This is usually obtained by asking the patient a series of questions about their past medical conditions, current health status, family medical history, lifestyle habits, and any medications they are taking. The information collected in the medical history helps healthcare professionals to diagnose, treat, and manage the patient's health concerns more effectively. It is also an essential part of continuity of care, as it provides valuable insights into the patient's health over time.

... -3. The second non-visual arrestin cloned was first termed β-arrestin-2 (retroactively changing the name of β-arrestin ... In mammals, arrestin-1 and arrestin-4 are largely confined to photoreceptors, whereas arrestin-2 and arrestin-3 are ubiquitous ... Arrestin-2 was the first non-visual arrestin cloned. It was first named β-arrestin simply because of the two GPCRs available in ... Arrestin-4 was cloned by two groups and termed cone arrestin, after photoreceptor type that expresses it, and X-arrestin, after ...
... β-arrestins (also referred to as visual and non-visual arrestins) and Vps26-like arrestins proteins. The α-Arrestins are an ... The arrestin family of proteins is subdivided into α-arrestins (also referred to as arrestin-related trafficking adaptors (ARTs ... It is unclear if α-arrestins lack each of these structural features thought to distinguish the β-arrestins from the α-arrestins ... β-arrestins contain a polar core flanked on both sides by the arrestin N- and C-terminal fold domains. They also contain ...
Beta-arrestin-2, also known as arrestin beta-2, is an intracellular protein that in humans is encoded by the ARRB2 gene. ... Arrestin beta 2 is crucial for the development of tolerance to morphine and other opioids. Arrestin beta 2 has been shown to ... Arrestin beta 2, like arrestin beta 1, was shown to inhibit beta-adrenergic receptor function in vitro. It is expressed at high ... Members of arrestin/beta-arrestin protein family are thought to participate in agonist-mediated desensitization of G protein- ...
Arrestin, beta 1, also known as ARRB1, is a protein which in humans is encoded by the ARRB1 gene. Members of arrestin/beta- ... "Entrez Gene: ARRB1 arrestin, beta 1". Peterson YK, Luttrell LM (July 2017). "The Diverse Roles of Arrestin Scaffolds in G ... "Substance P-induced trafficking of beta-arrestins. The role of beta-arrestins in endocytosis of the neurokinin-1 receptor". The ... Beta-arrestin has been shown to play a role as a scaffold that binds intermediates and may direct G-protein signaling by ...
1997). "Arrestin/clathrin interaction. Localization of the arrestin binding locus to the clathrin terminal domain". J. Biol. ...
S-arrestin is a protein that in humans is encoded by the SAG gene. Members of arrestin/beta-arrestin protein family are thought ... 1995). "Chromosome mapping of the human arrestin (SAG), beta-arrestin 2 (ARRB2), and beta-adrenergic receptor kinase 2 (ADRBK2 ... S-arrestin, also known as S-antigen, is a major soluble protein in photoreceptor cells that is involved in desensitization of ... Additionally, S-arrestin is highly antigenic, and is capable of inducing experimental autoimmune uveoretinitis. Mutations in ...
Crystal structure of rhodopsin bound to arrestin determined by femtosecond X-ray laser Nature 526: 561-567 T. Hua, K. Vemuri, M ... and the human Rhodopsin-Arrestin complex. 2016: The marijuana receptor-human Cannabinoid receptor type 1 (CB1) and the human C- ...
Bruchas MR, Macey TA, Lowe JD, Chavkin C (June 2006). "Kappa opioid receptor activation of p38 MAPK is GRK3- and arrestin- ... β-arrestin antagonist Nalfurafine (Remitch), which was introduced in 2009, is the first selective KOR agonist to enter clinical ... β-arrestin antagonist Zyklophin - selective peptide antagonist; dynorphin A analogue KSC-12-192 - selective, biased ligand: G ... β-arrestin antagonist Amentoflavone - non-selective; naturally-occurring AT-076 - non-selective, likely long acting; JDTic ...
"Prolonged photoresponses in transgenic mouse rods lacking arrestin". Nature. 389 (6650): 505-509. Bibcode:1997Natur.389..505X. ...
Unlike most μ-opioid receptor agonists, herkinorin does not promote the recruitment of β-arrestin 2 to the intracellular domain ... April 2008). "Herkinorin analogues with differential beta-arrestin-2 interactions". Journal of Medicinal Chemistry. 51 (8): ... arrestin interactions or receptor internalization". Molecular Pharmacology. 71 (2): 549-57. doi:10.1124/mol.106.028258. PMC ... and some other analogues related to herkinorin can recruit β-arrestins. Kurkinorin Salvinorin B methoxymethyl ether RB-64 ...
2006). "Stable rhodopsin/arrestin complex leads to retinal degeneration in a transgenic mouse model of autosomal dominant ... In this research null mutations in the rhodopsin kinase and arrestin genes, each of which plays a role in terminating rhodopsin ... Besides this, the stable rhodopsin and arrestin complexes are shown to mislocalize and accumulate in the inner segments of rod ... The R135 mutant rhodopsin is noted to form stable complex with arrestin and undergo endocytosis resulting in aberrant endocytic ...
While it binds to the same receptors as opioid analgesics, TRV734 has very weak β-arrestin recruitment, unlike other available ... Violin, Jonathan D.; Lefkowitz, Robert J. (2007). "Β-Arrestin-biased ligands at seven-transmembrane receptors". Trends in ... ß-arrestin-biased ligand at the angiotensin II type I receptor, in healthy and heart failure canines: A novel therapeutic ... but Trevena hopes to avoid this with TRV250 by bypassing the β-arrestin pathway. TRV734 is an oral follow-up to the injected ...
Kim Y, Kim H, Lee J, Lee JK, Min SJ, Seong J, Rhim H, Tae J, Lee HJ, Choo H (August 2018). "Discovery of β-Arrestin Biased ... beta-arrestin recruitment, and receptor internalization. Inactivating antagonists all likely interact with the 5-HT7 receptor ... role of G protein-coupled receptor kinases and arrestins in receptor desensitization and resensitization". Receptors & Channels ...
He is the author of fundamental scientific works in pharmacology of dopamine, β-Arrestins and NMDA receptors. He is a pioneer ... Beaulieu JM, Sotnikova TD, Marion S, Lefkowitz RJ, Gainetdinov RR, Caron MG (2005-07-29). "An Akt/β-Arrestin 2/PP2A Signaling ... "Enhanced Morphine Analgesia in Mice Lacking β-Arrestin 2". Science. 286 (5449): 2495-2498. doi:10.1126/science.286.5449.2495. ...
Kim YM, Barak LS, Caron MG, Benovic JL (May 2002). "Regulation of arrestin-3 phosphorylation by casein kinase II". The Journal ...
Lohse, Martin J.; Benovic, Jeffrey L.; Codina, Juan; Caron, Marc G.; Lefkowitz, Robert J. (22 June 1990). "β-Arrestin: a ... While working with Robert Lefkowitz at Duke University he discovered beta-arrestins, proteins that regulate the function of ...
In many cases, arrestin's binding to the receptor is a prerequisite for translocation. For example, beta-arrestin bound to β2- ... Arrestin linking: The phosphorylated receptor can be linked to arrestin molecules that prevent it from binding (and activating ... Upon GRK phosphorylation, the GPCR's affinity for β-arrestin (β-arrestin-1/2 in most tissues) is increased, at which point β- ... Once β-arrestin is bound to a GPCR, it undergoes a conformational change allowing it to serve as a scaffolding protein for an ...
Reiter, Eric; Ahn, Seungkirl; Shukla, Arun K.; Lefkowitz, Robert J. (11 January 2012). "Molecular Mechanism of β-Arrestin- ... India portal Biology portal Cell signaling Arrestin Membrane proteins Please see Selected bibliography section "Arun K. Shukla ... "Functional specialization of β-arrestin interactions revealed by proteomic analysis". Proceedings of the National Academy of ... "Global phosphorylation analysis of β-arrestin-mediated signaling downstream of a seven transmembrane receptor (7TMR)". ...
... via protein kinase phosphorylation or b-arrestin-dependent internalization. A study was conducted where a point mutation was ...
van Koppen, C. J.; Jakobs, K. H. Arrestin-Independent Internalization of G Protein-Coupled Receptors. Molecular Pharmacology ... of β-arrestin and the activation of the p38 MAPK and other secondary signaling cascades that are dependent on β-arrestin. INTA ... to form a conformation to block the recruitment of a protein family known as the β-arrestins. These proteins are responsible ...
Differential regulation of beta-arrestins 1 and 2". The Journal of Biological Chemistry. 277 (52): 50422-30. doi:10.1074/jbc. ...
August 2016). "GPCR-G Protein-β-Arrestin Super-Complex Mediates Sustained G Protein Signaling". Cell. 166 (4): 907-919. doi: ... "Absence of a stable secondary structure is not a limitation for photoswitchable inhibitors of β-arrestin/β-Adaptin 2 protein- ...
... which has been observed for arrestins. Moreover, Vps26 does not have similar sequences as arrestins for GPCR and phospholipid ... Both Vps26 and arrestins are composed of two structurally related β-sheet domains forming extensive interfaces with each other ... Vps26 is a 38-kDa subunit that has a two-lobed structure with a polar core that resembles the arrestin family of trafficking ... Shi H, Rojas R, Bonifacino JS, Hurley JH (2006). "The retromer subunit Vps26 has an arrestin fold and binds Vps35 through its C ...
The V2R continues to activate Gs after being internalized by β-arrestin rather than being desensitized. This internalized Gs ... "GPCR-G Protein-β-Arrestin Super-Complex Mediates Sustained G Protein Signaling". Cell. 166 (4): 907-19. doi:10.1016/j.cell. ... signaling by V2R is explained by the receptors ability to form "mega-complexes" consisting of a single V2R, β-arrestin, and ...
Arrestin-C, also known as retinal cone arrestin-3, is a protein that in humans is encoded by the ARR3 gene. Arrestin GRCh38: ... "Entrez Gene: ARR3 arrestin 3, retinal (X-arrestin)". Craft CM, Whitmore DH, Wiechmann AF (1994). "Cone arrestin identified by ... Murakami A, Yajima T, Sakuma H, McLaren MJ, Inana G (Dec 1993). "X-arrestin: a new retinal arrestin mapping to the X chromosome ... 2002). "Mouse cone arrestin expression pattern: light induced translocation in cone photoreceptors". Mol. Vis. 8: 462-71. PMID ...
May 2009). "Lipid G protein-coupled receptor ligand identification using beta-arrestin PathHunter assay". The Journal of ... however this result was not confirmed in a β-arrestin recruitment assay. Mice lacking GPR3 were found to develop late-onset ...
"Activity-dependent internalization of smoothened mediated by beta-arrestin 2 and GRK2". Science. 306 (5705): 2257-60. Bibcode: ...
December 2004). "Activity-dependent internalization of smoothened mediated by beta-arrestin 2 and GRK2". Science. 306 (5705): ...
These include mutations in the arrestin gene or the rhodopsin kinase gene. The condition is more frequent in individuals of ...
Moreover Arrestin binding to a phosphorylated, active receptor also enables receptor signaling through arrestin partner ... which promotes the binding of an arrestin protein to the receptor. Arrestin binding to a phosphorylated, active receptor ... Consequently the GRK/arrestin system serves as a signaling switch for G protein-coupled receptors. GRK4 is most highly ... Gurevich VV, Gurevich EV (2019). "GPCR Signaling Regulation: The Role of GRKs and Arrestins". Front Pharmacol. 10: 125. doi: ...
Arrestin-3. The second non-visual arrestin cloned was first termed β-arrestin-2 (retroactively changing the name of β-arrestin ... In mammals, arrestin-1 and arrestin-4 are largely confined to photoreceptors, whereas arrestin-2 and arrestin-3 are ubiquitous ... Arrestin-2 was the first non-visual arrestin cloned. It was first named β-arrestin simply because of the two GPCRs available in ... Arrestin-4 was cloned by two groups and termed cone arrestin, after photoreceptor type that expresses it, and X-arrestin, after ...
The PathHunter® eXpress OPRK1 U2OS β-Arrestin GPCR Assay measures OPRK1 (GPCR) activity via recruitment of β-Arrestin 2. ... Home / Assay Kits / eXpress Assay Kits / PathHunter® eXpress OPRK1 U2OS β-Arrestin GPCR Assay. ... Youre viewing: PathHunter® eXpress OPRK1 U2OS β-Arrestin GPCR Assay $1,789.00 - $5,989.00 ... The cells included overexpress PK-tagged OPRK1 and EA-tagged β-Arrestin-2. Activation of OPRK1 stimulates the recruitment of β- ...
Arrestins. Arrestins (abbreviated Arr) are a family of proteins which are important in the regulation of signal transduction G- ...
"Sortase ligation enables homogeneous GPCR phosphorylation to reveal diversity in β-arrestin coupling." Proc Natl Acad Sci U S A ... "Sortase ligation enables homogeneous GPCR phosphorylation to reveal diversity in β-arrestin coupling." Proc Natl Acad Sci U S A ... Sortase ligation enables homogeneous GPCR phosphorylation to reveal diversity in β-arrestin coupling.. Publication , Journal ... Sortase ligation enables homogeneous GPCR phosphorylation to reveal diversity in β-arrestin coupling. Proc Natl Acad Sci U S A ...
beta-Arrestin 2 / genetics* * rho-Associated Kinases / genetics* * rhoA GTP-Binding Protein / genetics* ...
Si e mbajti Gjykata një muaj pa firmosur urdhër-arrestin/ Prapaskenat e drejtësisë për prangosjen Mirel Mërtirit ...
Internalization of gonadotropin-releasing hormone receptors (GnRHRs): does arrestin binding to the C-terminal tail target ... including the critical role of receptor kinases and arrestin, comparatively little is known about the processes determining the ...
2006) Arrestin is required for agonist-induced trafficking of voltage-dependent Ca2+ channels. J Biol Chem 281:31131-31141. ... Because β-arrestins are required for c-Src targeting to GPCRs (Miller et al., 2000), we first examined whether there is ... β-Arrestins target several proteins to μ receptors, including c-Src, which participates in μ receptor signaling (Kato et al., ... β-Arrestins bind to agonist-activated G-protein-coupled receptors regulating signaling events and initiating endocytosis. In β- ...
Title: Vascular Endothelial Growth Factor Receptor 3 Regulates Endothelial Function Through β-Arrestin 1. ...
A topless womans lawsuit against the NYPD is making the Big Apples po-pos look like a bunch of boobs when it comes to melons. Jessica Krigsman, a 24-year-old burlesque dancer, was sunbathing topless in a park when two officers ordered her to put her shirt back on. Krigsman refused, asserted her legal rights, and was arrested -- but the police got the law wrong in a big, busty way.
A man wanted in an apparently unprovoked fatal shooting aboard a New York City subway train is under arrest.
Crystal structure of Xenopus Arrestin 1 suggests multiple, competing dimer interfaces Cassandra Barnes; David Salom; Michael ...
Since 2007, Jezebel has been the Internets most treasured source for everything celebrities, sex, and politics...with teeth.
A beta-arrestin 2 signaling complex mediates lithium action on behavior. Cell. 2008 Jan 11. 132(1):125-36. [QxMD MEDLINE Link] ... Glycogen synthase kinase-3 is essential for ß-arrestin-2 complex formation and lithium-sensitive behaviors in mice. J Clin ...
Surveying non-visual arrestins reveals allosteric interactions between functional sites.﻽. Seckler JM, Robinson EN, Lewis SJ, ...
Family b.1.18.11: Arrestin/Vps26-like [81291] (2 proteins). *. Protein Arrestin [49244] (3 species). duplication: contains ... d1g4ma1 b.1.18.11 (A:5-175) Arrestin {Cow (Bos taurus), beta-arrestin 1 [TaxId: 9913]} ... PDB Description: crystal structure of bovine beta-arrestin 1. PDB Compounds: (A:) beta-arrestin1. SCOPe Domain Sequences for ... Species Cow (Bos taurus), beta-arrestin 1 [TaxId:9913] [69169] (6 PDB entries). ...
Officials have said packages turned up at the CIAs mail-sorting facility, a White House mail-sorting facility in suburban Washington, a Navy facility in Dahlgren, Virginia, and two facilities at Fort Belvoir, Virginia - the National Geospatial-Intelligence Agency and another defense university.
A Portsmouth man was arrested Tuesday and charged with felony assault and assault and battery in connection to an alleged stabbing the previous evening in the 6000 block of Bradford Drive.. A 48-year-old Suffolk man was treated by Suffolk Fire and Rescue personnel for multiple stab wounds and was taken by ambulance to a local hospital with injuries considered non-life threatening, according to a city news release.. Following an investigation by Suffolk Police, Paul Vincent Bolton Jr., 56, of Portsmouth, was arrested and charged in connection to the incident.. ...
Comparison With the Previous Spanish Study. The study performed previously in Spain involved 283 patients with CA and/or respiratory arrest occurring both in hospital and out of hospital.3 One hundred thirty-five children had in-hospital CA (71.1% of them in the pediatric intensive care unit). Survival was 25.9%, with a statistically significant difference (P<.001) between both studies. Duration of CPR greater than 20min was the factor most strongly associated with mortality.3. DISCUSSION. Our study confirms that, although in-hospital CA in children is associated with a high mortality rate, survival (41%) has significantly improved in recent years.. In a previous study carried out in Spain, survival to discharge after in-hospital CA was 25.9%. This difference may be due to a number of factors. Over the past decade, there has been a considerable effort to provide training in pediatric CPR, coordinated by the Spanish Pediatric Cardiopulmonary Resuscitation Group, with the development of a number ...
The bile acid receptor TGR5 does not interact with $beta$-arrestins or traffic to endosomes but transmits sustained signals ... Endothelin-converting enzyme 1 and $beta$-arrestins exert spatiotemporal control of substance P-induced inflammatory signals. ... Multisite phosphorylation is required for sustained interaction with GRKs and arrestins during rapid mu-opioid receptor ... Multisite phosphorylation is required for sustained interaction with GRKs and arrestins during rapid mu-opioid receptor ...
... www.thejournal.ie/further-arrest-in-connection-with-fatal-roscommon-fire-250825-Oct2011/?embedpost=250825&width=600&height=460 ... www.thejournal.ie/further-arrest-in-connection-with-fatal-roscommon-fire-250825-Oct2011/?embedpost=250825&width=400&height=460 ... www.thejournal.ie/further-arrest-in-connection-with-fatal-roscommon-fire-250825-Oct2011/?embedpost=250825&width=300&height=460 ...
Mumbai Polices crime branch arrested a 22-year-old man from Madhya Pradesh, making it the sixth arrest in connection with kidnapping of a Mumbai-based builder
beta}-Arrestin-biased {beta}-adrenergic signaling promotes extinction learning of cocaine reward memory. Extinction learning of ...
The top-notch Jerusalem Police Central Unit has been assigned to lead the investigation. Senior officers have promised that every possible effort will be made to solve this murder. President Shimon Peres stated that those responsible will be tried and punished. Israeli leaders have widely condemned the killing of the Palestinian youth, whoever was responsible, and Prime Minister Binyamin Netanyahu vowed those responsible would be brought to justice.. In a separate incident, Abu Khdeirs 15-year-old cousin Tariq, a US citizen was beaten by police during clashes in Jerusalem on Thursday. Tariqs parents, Suha and Salah, said he was detained but had been treated at an Israeli hospital. They released photos showing his face swollen and badly bruised. An Israeli police spokeswoman said Tariq Abu Khdeir had resisted arrest and attacked police officers. He was detained with a slingshot in his possession, along with six other protesters, including some armed with knives, she said, adding that several ...
Surfactant protein-A modulates LPS-induced TLR4 localization and signaling via β-arrestin 2. ...
A 25-year-old man has been accused of setting a fire that resulted in the evacuation of a massive apartment complex in Vestal.
It was hot in McCleary June 26, 2009. Lindsey Baum, just weeks shy of her 11th birthday, had spent part of the day beating the heat with a lot of neighborhood kids at a pool party blocks from her …
West Virginia University Police have arrested a man they suspect of brandishing a knife on Belmar Avenue Wednesday night (March 10) near, but not on the Morgantown campus. The University issued a WVU Alert that night in response to the incident.
In addition, proteins called arrestins bind metarhodopsin and prevent it from activating more Gq. ...
The incarceration of trans woman Nikita Dragun in a mens jail is part of a much wider trend of transgender individuals being placed in jails and prisons that dont align with their gender identity.
  • Arrestins (abbreviated Arr) are a small family of proteins important for regulating signal transduction at G protein-coupled receptors. (wikipedia.org)
  • In addition to GPCRs, arrestins bind to other classes of cell surface receptors and a variety of other signaling proteins. (wikipedia.org)
  • Arrestins block GPCR coupling to G proteins in two ways. (wikipedia.org)
  • Arrestins (abbreviated Arr) are a family of proteins which are important in the regulation of signal transduction G-protein coupled receptors, which at first was discovered, as part of a conserved two step mechanism for regulating the activity of G protein-coupled receptors (GPCR) in rhodopsin visual system by Ursula Kuhn found Scott court, and β-called Global Martin J. Lohse system and kidney and colleagues. (arrestins.com)
  • The ability of G protein-coupled receptors (GPCRs) to initiate complex cascades of cellular signaling is governed by the sequential coupling of three main transducer proteins, G protein, GPCR kinase (GRK), and β-arrestin. (duke.edu)
  • Here we compare the allosteric interactions of G proteins and β-arrestins with GPCRs' transmembrane cores by using the enzyme sortase to ligate a synthetic phosphorylated peptide onto the carboxyl terminus of three different receptors. (duke.edu)
  • We subsequently found that all three known arrestins (beta-arrestin, arrestin-3, and visual arrestin) bound specifically to fusion proteins encoding the i3 loop of the 5-HT(2A) receptor. (nih.gov)
  • Dual-label immunofluorescence confocal microscopic studies of rat cortex indicated that many cortical pyramidal neurons coexpressed arrestins (beta-arrestin or arrestin-3) and 5-HT2A receptors, particularly in intracellular vesicles. (nih.gov)
  • Arrestins were first discovered as a part of a conserved two-step mechanism for regulating the activity of G protein-coupled receptors (GPCRs) in the visual rhodopsin system by Hermann Kühn, Scott Hall, and Ursula Wilden and in the β-adrenergic system by Martin J. Lohse and co-workers. (wikipedia.org)
  • It was first named β-arrestin simply because of the two GPCRs available in purified form at the time, rhodopsin and β2-adrenergic receptor, it showed preference for the latter. (wikipedia.org)
  • The second non-visual arrestin cloned was first termed β-arrestin-2 (retroactively changing the name of β-arrestin into β-arrestin-1), even though by that time it was clear that non-visual arrestins interact with hundreds of different GPCRs, not just with β2-adrenergic receptor. (wikipedia.org)
  • It was later renamed visual arrestin, but when another cone-specific visual subtype was cloned the term rod arrestin was coined. (wikipedia.org)
  • Arrestin-2 was the first non-visual arrestin cloned. (wikipedia.org)
  • Arrestin binding to the receptor blocks further G protein-mediated signaling and targets receptors for internalization, and redirects signaling to alternative G protein-independent pathways, such as β-arrestin signaling. (wikipedia.org)
  • Our results demonstrate (a) that the i3 loop of the 5-HT2A receptor represents a structurally ordered domain composed of alpha-helical and beta-loop, -turn, and -sheet regions, (b) that this loop interacts with arrestins in vitro, and is hence active, and (c) that arrestins are colocalized with 5-HT2A receptors in vivo. (nih.gov)
  • Scholars@Duke publication: Sortase ligation enables homogeneous GPCR phosphorylation to reveal diversity in β-arrestin coupling. (duke.edu)
  • For example, GRK-mediated receptor phosphorylation recruits and induces conformational changes in β-arrestin, which facilitates coupling to the GPCR transmembrane core. (duke.edu)
  • The systematic arrestin name (1-4) plus the most widely used aliases for each arrestin subtype are listed in bold below: Arrestin-1 was originally identified as the S-antigen (SAG) causing uveitis (autoimmune eye disease), then independently described as a 48 kDa protein that binds light-activated phosphorylated rhodopsin before it became clear that both are one and the same. (wikipedia.org)
  • First, arrestin binding to the cytoplasmic face of the receptor occludes the binding site for heterotrimeric G-protein, preventing its activation (desensitization). (wikipedia.org)
  • The thioredoxin-interacting protein (TXNIP) is a multi-functional protein of the alpha-arrestin family implicated in redox regulation, glucose uptake, cell proliferation, and activation of NLRP3. (cdc.gov)
  • Arrestin quenches G-protein activation by binding to phosphorylated photolyzed rhodopsin. (bvsalud.org)
  • Multisite phosphorylation is required for sustained interaction with GRKs and arrestins during rapid mu-opioid receptor desensitization Science Signaling. (nottingham.ac.uk)
  • GRK phosphorylation specifically prepares the activated receptor for arrestin binding. (wikipedia.org)
  • Second, arrestin links the receptor to elements of the internalization machinery, clathrin and clathrin adaptor AP2, which promotes receptor internalization via coated pits and subsequent transport to internal compartments, called endosomes. (wikipedia.org)
  • The strength of arrestin-receptor interaction plays a role in this choice: tighter complexes tend to increase the probability of receptor degradation (Class B), whereas more transient complexes favor recycling (Class A), although this "rule" is far from absolute. (wikipedia.org)
  • Using random peptide phage libraries, we identified several arrestin-like sequences as i3-interacting peptides. (nih.gov)
  • Arrestin-4 was cloned by two groups and termed cone arrestin, after photoreceptor type that expresses it, and X-arrestin, after the chromosome where its gene resides. (wikipedia.org)
  • Conserved positions of multiple introns in its gene and those of our arrestin subtypes suggest that they all evolved from this ancestral arrestin. (wikipedia.org)
  • One or more arrestin is expressed in virtually every eukaryotic cell. (wikipedia.org)
  • GPCR function is modulated by a pair of proteins known as beta-arrestin-1 and -2 ( barr1 and barr2, respectively), which can terminate GPCR signaling and/or mediate GPCR-independent signaling. (nih.gov)
  • In the stressed male rat, the receptors interacted with internal proteins called arrestins, enabling some to retreat into the cell's interior, where they couldn't bind with the hormone. (nih.gov)
  • Although the arrestin proteins are present in the female neurons, the receptors did not interact with them. (nih.gov)
  • 16. Differential conformational requirements for activation of G proteins and the regulatory proteins arrestin and G protein-coupled receptor kinase in the G protein-coupled receptor for parathyroid hormone (PTH)/PTH-related protein. (nih.gov)
  • Structural studies including determination of 3D structures of ligands, receptors, receptors with associated G-proteins, beta-arrestin etc. (nih.gov)
  • GRK1-dependent phosphorylation of S and M opsins and their binding to cone arrestin during cone phototransduction in the mouse retina. (nih.gov)
  • Activated ß-arrestin-1 (yellow) binds a G-protein coupled receptor (green) that crosses the cell membrane (gray). (nih.gov)
  • To further elucidate mechanisms of arrestin-dependent regulation of G protein-coupled receptor processing, we examined the effects of altering the receptor-arrestin complex on ternary complex formation and cellular trafficking of the N-formyl peptide receptor by studying two active arrestin-2 mutants (truncated arrestin-2 [1-382], and arrestin-2 I386A, V387A, F388A). (unm.edu)
  • Furthermore, expression of arrestin-2 I386A/V387A/F388A but not arrestin-2 [1-382] inhibited recycling of the N-formyl peptide receptor, reflecting an expanded role for arrestins in G protein-coupled receptor processing and trafficking. (unm.edu)
  • Melanocytes from different donors expressed different levels of the G protein-coupled receptor kinases (GRKs) 2, 3, 5, and 6, as well as β-arrestin 1. (nih.gov)
  • Arrestin quenches G-protein activation by binding to phosphorylated photolyzed rhodopsin. (nih.gov)
  • Recent studies have highlighted the emergence of a class of G protein-coupled receptors that are internalized in an arrestin-independent manner. (unm.edu)
  • Activation of MCHR2 stimulates the recruitment of β-Arrestin 2 and produces EFC signal. (discoverx.com)
  • Using permanent and primary human bronchial epithelial (HBE) cells at air-liquid interface, we show that DEPs activate the human MMP-1 gene via RAS and subsequent activation of RAF-MEK-ERK1/2 mitogen-activated protein kinase signaling, which can be scaffolded by β-arrestins. (nih.gov)
  • The gene, arrestin domain containing 5 ( ARRDC5 ) is present in several mammalian species and controls the last step in sperm maturation. (nih.gov)
  • A previous study found that overactivity and inactivation of another gene in the arrestin domain containing family, ARRDC4 , found in the male reproductive tract, resulted in sperm with less ability to move and less ability to fertilize an egg. (nih.gov)
  • Compared to previously determined inactive state structures, activated β-arrestin-1 has pronounced structural changes. (nih.gov)
  • These scientists found similar changes between the active and inactive states of arrestin p44. (nih.gov)
  • The scientists were able to capture β-arrestin-1 in its active state and form crystals to determine its structure, as reported online in Nature on April 21, 2013. (nih.gov)