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Membrane Estrogen Receptor
Membrane estrogen receptors (mERs) are a group of receptor (biochemistry), receptors which bind estrogen. Unlike nuclear estrogen receptors, which mediate their effects via slower Genome, genomic mechanisms, mERs are cell surface receptors that rapidly alter cell signaling via modulation of intracellular Signal transduction, signaling cascades. Nuclear estrogen receptors such as ERα and ERβ become mERs through palmitoylation, a post-translational modification that enhances ER association with Caveolin 1, caveolin-1 to enable trafficking of ERs to the membrane or membrane caveolae. Other putative mERs include GPER (GPR30), GPRC6A, ER-X, ERx and Gq-mER, Gq-mER. Structure-function relationship In mice and humans, ERβ localization in the plasma membrane occurs after palmitoylation on cysteine 418. Dimerization of mERs appears necessary for their function in rapid cell signaling. Signaling mechanisms G-protein coupled receptors Various electrophysiological studies support E2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Receptor (biochemistry)
In biochemistry and pharmacology, receptors are chemical structures, composed of protein, that receive and Signal_transduction, transduce signals that may be integrated into biological systems. These signals are typically chemical messengers which bind to a receptor and produce physiological responses, such as a change in the electrophysiology, electrical activity of a cell. For example, GABA, an inhibitory neurotransmitter, inhibits electrical activity of neurons by binding to GABAA receptor, GABA receptors. There are three main ways the action of the receptor can be classified: relay of signal, amplification, or integration. Relaying sends the signal onward, amplification increases the effect of a single ligand (biochemistry), ligand, and integration allows the signal to be incorporated into another biochemical pathway. Receptor proteins can be classified by their location. Cell surface receptors, also known as transmembrane receptors, include ligand-gated ion channels, G prote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GPER
G protein-coupled estrogen receptor 1 (GPER), also known as G protein-coupled receptor 30 (GPR30), is a protein that in humans is encoded by the ''GPER'' gene. GPER binds to and is activated by the female sex hormone estradiol and is responsible for some of the rapid effects that estradiol has on cells. Discovery The classical estrogen receptors first characterized in 1958 are water-soluble proteins located in the interior of cells that are activated by estrogenenic hormones such as estradiol and several of its metabolites such as estrone or estriol. These proteins belong to the nuclear hormone receptor class of transcription factors that regulate gene transcription. Since it takes time for genes to be transcribed into RNA and translated into protein, the effects of estrogens binding to these classical estrogen receptors is delayed. However, estrogens are also known to have effects that are too fast to be caused by regulation of gene transcription. In 2005, it was discove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G Protein-coupled Receptors
G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large protein family, group of evolutionarily related proteins that are cell surface receptors that detect molecules outside the cell (biology), cell and activate cellular responses. They are coupled with G proteins. They pass through the cell membrane seven times in the form of six loops (three extracellular loops interacting with ligand molecules, three intracellular loops interacting with G proteins, an N-terminus, N-terminal extracellular region and a C-terminal intracellular region) of amino acid residues, which is why they are sometimes referred to as seven-transmembrane receptors. Text was copied from this source, which is available under Attribution 2.5 Generic (CC BY 2.5) licence/ref> Ligands can bind either to the extracellular N-terminus and loops (e.g. glutama ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estrogen Receptor
Estrogen receptors (ERs) are proteins found in cell (biology), cells that function as receptor (biochemistry), receptors for the hormone estrogen (17β-estradiol). There are two main classes of ERs. The first includes the intracellular estrogen receptors, namely ERα and ERβ, which belong to the nuclear receptor family. The second class consists of membrane estrogen receptors (mERs), such as GPER (GPR30), ER-X, and Gq-mER, Gq-mER, which are primarily G protein-coupled receptors. This article focuses on the nuclear estrogen receptors (ERα and ERβ). Upon activation by estrogen, intracellular ERs undergo protein targeting, translocation to the nucleus where they bind to specific DNA sequences. As DNA-binding transcription factors, they regulate the activity of various genes. However, ERs also exhibit functions that are independent of their DNA-binding capacity. These non-genomic actions contribute to the diverse effects of estrogen signaling in cells. Estrogen receptors (ERs) b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membrane Steroid Receptor
Membrane steroid receptors (mSRs), also called extranuclear steroid receptors, are a class of cell surface receptors activated by endogenous steroids that mediate rapid, non-genomic signaling via modulation of intracellular signaling cascades. mSRs are another means besides classical nuclear steroid hormone receptors (SHRs) for steroids to mediate their biological effects. SHRs can produce slow genomic responses or rapid, non-genomic responses in the case of mSRs. __TOC__ List of membrane steroid receptors Known groups of mSRs, by ligand, include: * Membrane sex steroid receptors ** Membrane androgen receptors (mARs) – GPRC6A, OXER1, ZIP9; TRPM8; Cav1.2, GPR133 ** Membrane estrogen receptors (mERs) – GPER, ER-X, ERx, Gq-mER; Nav1.2; palmitoylated nuclear receptors ** Membrane progesterone receptors (mPRs) – PAQRs ( mPRα, mPRβ, mPRγ, mPRδ, mPRϵ); PGRMC1, PGRMC2; * Membrane corticosteroid receptors ** Membrane glucocorticoid receptors (mGRs) – caveolin-a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angiotensin II Receptor
The angiotensin II receptors, (ATR1) and (ATR2), are a class of G protein-coupled receptors with angiotensin II as their ligands. They are important in the renin–angiotensin system: they are responsible for the signal transduction of the vasoconstricting stimulus of the main effector hormone, angiotensin II. Structure The AT1 and AT2 receptors share a sequence identity of ~30%, but have a similar affinity for angiotensin II, which is their main ligand. Members Overview table AT1 The AT1 receptor is the best elucidated angiotensin receptor. Location within the body The AT1 subtype is found in the heart, blood vessels, kidney, adrenal cortex, lung and circumventricular organs of brain, basal ganglia, brainstem and mediates the vasoconstrictor effects. Mechanism The angiotensin receptor is activated by the vasoconstricting peptide angiotensin II. The activated receptor in turn couples to Gq/11 and Gi/o and thus activates phospholipase C and increases the cytosolic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GIRK
The G protein-coupled inwardly rectifying potassium channels (GIRKs) are a family of lipid-gated inward-rectifier potassium ion channels which are activated (opened) by the signaling lipid PIP2 and a signal transduction cascade starting with ligand-stimulated G protein-coupled receptors (GPCRs). GPCRs in turn release activated G-protein βγ- subunits ( Gβγ) from inactive heterotrimeric G protein complexes (Gαβγ). Finally, the Gβγ dimeric protein interacts with GIRK channels to open them so that they become permeable to potassium ions, resulting in hyperpolarization of the cell membrane. G protein-coupled inwardly rectifying potassium channels are a type of G protein-gated ion channels because of this direct interaction of G protein subunits with GIRK channels. The activation likely works by increasing the affinity of the channel for PIP2. In high concentration PIP2 activates the channel absent G-protein, but G-protein does not activate the channel absent PIP2. GIRK ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABAB Receptor
GABAB receptors (GABABR) are G protein-coupled receptor, G-protein coupled receptors for gamma-aminobutyric acid (GABA), therefore making them metabotropic receptors, that are linked via G-proteins to potassium channels. The changing potassium concentrations hyperpolarize the cell at the end of an action potential. The reversal potential of the GABAB-mediated IPSP (inhibitory postsynaptic potential) is −100 mV, which is much more hyperpolarized than the GABAA receptor, GABAA IPSP. GABAB receptors are found in the central nervous system and the autonomic nervous system, autonomic division of the peripheral nervous system. The receptors were first named in 1981 when their distribution in the CNS was determined, which was determined by Norman Bowery and his team using radioactively labelled baclofen. Functions GABABRs stimulate the opening of Potassium channel, K+ channels, specifically G protein-coupled inwardly-rectifying potassium channel, GIRKs, which brings the neuro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Kinase A
In cell biology, protein kinase A (PKA) is a family of serine-threonine kinases whose activity is dependent on cellular levels of cyclic AMP (cAMP). PKA is also known as cAMP-dependent protein kinase (). PKA has several functions in the cell, including regulation of glycogen, sugar, and lipid metabolism. It should not be confused with 5'-AMP-activated protein kinase (AMP-activated protein kinase). History Protein kinase A, more precisely known as adenosine 3',5'-monophosphate (cyclic AMP)-dependent protein kinase, abbreviated to PKA, was discovered by chemists Edmond H. Fischer and Edwin G. Krebs in 1968. They won the Nobel Prize in Physiology or Medicine in 1992 for their work on phosphorylation and dephosphorylation and how it relates to PKA activity. PKA is one of the most widely researched Protein kinase, protein kinases, in part because of its uniqueness; out of 540 different protein kinase genes that make up the human kinome, only one other protein kinase, casein kinase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gq-mER
The Gq-coupled membrane estrogen receptor (Gq-mER) is a G protein-coupled receptor present in the hypothalamus that has not yet been cloned. It is a membrane-associated receptor that is Gq-coupled to a phospholipase C–protein kinase C–protein kinase A (PLC–PKC–PKA) pathway. The receptor has been implicated in the control of energy homeostasis. Gq-mER is bound and activated by estradiol, and is a putative membrane estrogen receptor (mER). A nonsteroidal diphenylacrylamide derivative, STX, which is structurally related to 4-hydroxytamoxifen (afimoxifene), is an agonist of the receptor with greater potency than estradiol (20-fold higher affinity) that has been discovered. Fulvestrant (ICI-182,780) has been identified as an antagonist of Gq-mER, but is not selective. See also * Estrogen receptor * GPER G protein-coupled estrogen receptor 1 (GPER), also known as G protein-coupled receptor 30 (GPR30), is a protein that in humans is encoded by the ''GPER'' gene. GPER bind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ER-X
ER-X is a membrane-associated receptor that is bound and activated by 17α-estradiol and 17β-estradiol and is a putative membrane estrogen receptor (mER). It shows sequence homology with ERα and ERβ and activates the MAPK/ERK pathway. The receptor is insensitive to the antiestrogen ICI-182,780 (fulvestrant). See also * ERx * GPER (GPR30) * Gq-mER * Estrogen receptor Estrogen receptors (ERs) are proteins found in cell (biology), cells that function as receptor (biochemistry), receptors for the hormone estrogen (17β-estradiol). There are two main classes of ERs. The first includes the intracellular estrogen ... References Human proteins Transmembrane receptors {{receptor-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
