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Urotensin-II
Urotensin-II (U-II) is a peptide ligand that is the strongest known vasoconstrictor. Because of the involvement of the UII system in multiple biological systems such as the cardiovascular, nervous, endocrine, and renal, it represents a promising target for the development of new drugs. In humans, Urotensin-2 is encoded by the ''UTS2'' gene. Discovery U-II was initially isolated from the neurosecretory system of the Goby fish (''Gillichthys mirabilis''). For many years it was thought that U-II does not exhibit significant effects in mammalian systems; a view quickly overturned when it was demonstrated that Goby U-II produces slow relaxation of mouse anococcygeus muscle, in addition to contraction of rat artery segments. In 1998, the genes for Pre-pro U-II were found in mammals proving that the peptide U-II did exist in mammals. Structure The U-II gene is located on chromosome 1p36. U-II peptide length varies between species due to the specific cleaving sites located at d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urotensin-II Receptor
The urotensin-2 receptor (UR-II-R) also known as GPR14 is a class A rhodopsin family G protein coupled-receptor (GPCR) that is 386 amino acids long which binds primarily to the neuropeptide urotensin II. /sup> The receptor quickly rose to prominence when it was found that when activated by urotensin II it induced the most potent vasoconstriction effect ever seen. While the precise function of the urotensin II receptor is not fully known it has been linked to cardiovascular effects, stress, and REM sleep. Ligands There are two known endogenous agonists for the urotensin II receptor. One is urotensin II whose mRNA is found in a variety of tissues including the brain and also blood vessels. It is a potent vasoconstrictor and can increase REM cycles. The other is urotensin II-Related Peptide (URP) which is found in a variety of tissues as well although at less concentrations then urotensin II. The one exception is in human reproductive tissue where the levels of URP are much highe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urotensin-II Receptor
The urotensin-2 receptor (UR-II-R) also known as GPR14 is a class A rhodopsin family G protein coupled-receptor (GPCR) that is 386 amino acids long which binds primarily to the neuropeptide urotensin II. /sup> The receptor quickly rose to prominence when it was found that when activated by urotensin II it induced the most potent vasoconstriction effect ever seen. While the precise function of the urotensin II receptor is not fully known it has been linked to cardiovascular effects, stress, and REM sleep. Ligands There are two known endogenous agonists for the urotensin II receptor. One is urotensin II whose mRNA is found in a variety of tissues including the brain and also blood vessels. It is a potent vasoconstrictor and can increase REM cycles. The other is urotensin II-Related Peptide (URP) which is found in a variety of tissues as well although at less concentrations then urotensin II. The one exception is in human reproductive tissue where the levels of URP are much highe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vasoconstriction
Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vessels. The process is particularly important in controlling hemorrhage and reducing acute blood loss. When blood vessels constrict, the flow of blood is restricted or decreased, thus retaining body heat or increasing vascular resistance. This makes the skin turn paler because less blood reaches the surface, reducing the radiation of heat. On a larger level, vasoconstriction is one mechanism by which the body regulates and maintains mean arterial pressure. Medications causing vasoconstriction, also known as vasoconstrictors, are one type of medicine used to raise blood pressure. Generalized vasoconstriction usually results in an increase in systemic blood pressure, but it may also occur in specific tissues, causing a localized reduction in bl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lysine
Lysine (symbol Lys or K) is an α-amino acid that is a precursor to many proteins. It contains an α-amino group (which is in the protonated form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −COO− form under biological conditions), and a side chain lysyl ((CH2)4NH2), classifying it as a basic, charged (at physiological pH), aliphatic amino acid. It is encoded by the codons AAA and AAG. Like almost all other amino acids, the α-carbon is chiral and lysine may refer to either enantiomer or a racemic mixture of both. For the purpose of this article, lysine will refer to the biologically active enantiomer L-lysine, where the α-carbon is in the ''S'' configuration. The human body cannot synthesize lysine. It is essential in humans and must therefore be obtained from the diet. In organisms that synthesise lysine, two main biosynthetic pathways exist, the diaminopimelate and α-aminoadipate pathways, which employ distinct e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brainstem
The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is continuous with the thalamus of the diencephalon through the tentorial notch, and sometimes the diencephalon is included in the brainstem. The brainstem is very small, making up around only 2.6 percent of the brain's total weight. It has the critical roles of regulating cardiac, and respiratory function, helping to control heart rate and breathing rate. It also provides the main motor and sensory nerve supply to the face and neck via the cranial nerves. Ten pairs of cranial nerves come from the brainstem. Other roles include the regulation of the central nervous system and the body's sleep cycle. It is also of prime importance in the conveyance of motor and sensory pathways from the rest of the brain to the body, and from the body back to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phospholipase C
Phospholipase C (PLC) is a class of membrane-associated enzymes that cleave phospholipids just before the phosphate group (see figure). It is most commonly taken to be synonymous with the human forms of this enzyme, which play an important role in eukaryotic cell physiology, in particular signal transduction pathways. Phospholipase C's role in signal transduction is its cleavage of phosphatidylinositol 4,5-bisphosphate (PIP2) into diacyl glycerol (DAG) and inositol 1,4,5-trisphosphate (IP3), which serve as second messengers. Activators of each PLC vary, but typically include heterotrimeric G protein subunits, protein tyrosine kinases, small G proteins, Ca2+, and phospholipids. There are thirteen kinds of mammalian phospholipase C that are classified into six isotypes (β, γ, δ, ε, ζ, η) according to structure. Each PLC has unique and overlapping controls over expression and subcellular distribution. Variants Mammalian variants The extensive number of functions exerte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Kinase C
In cell biology, Protein kinase C, commonly abbreviated to PKC (EC 2.7.11.13), is a family of protein kinase enzymes that are involved in controlling the function of other proteins through the phosphorylation of hydroxyl groups of serine and threonine amino acid residues on these proteins, or a member of this family. PKC enzymes in turn are activated by signals such as increases in the concentration of diacylglycerol (DAG) or calcium ions (Ca2+). Hence PKC enzymes play important roles in several signal transduction cascades. In biochemistry, the PKC family consists of fifteen isozymes in humans. They are divided into three subfamilies, based on their second messenger requirements: conventional (or classical), novel, and atypical. Conventional (c)PKCs contain the isoforms α, βI, βII, and γ. These require Ca2+, DAG, and a phospholipid such as phosphatidylserine for activation. Novel (n)PKCs include the δ, ε, η, and θ isoforms, and require DAG, but do not require Ca2+ for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gq Alpha Subunit
Gq protein alpha subunit is a family of heterotrimeric G protein alpha subunits. This family is also commonly called the Gq/11 (Gq/G11) family or Gq/11/14/15 family to include closely related family members. G alpha subunits may be referred to as Gq alpha, Gαq, or Gqα. Gq proteins couple to G protein-coupled receptors to activate beta-type phospholipase C (PLC-β) enzymes. PLC-β in turn hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) to diacyl glycerol (DAG) and inositol trisphosphate (IP3). IP3 acts as a second messenger to release stored calcium into the cytoplasm, while DAG acts as a second messenger that activates protein kinase C (PKC). Family members In humans, there are four distinct proteins in the Gq alpha subunit family: * Gαq is encoded by the gene GNAQ. * Gα11 is encoded by the gene GNA11. * Gα14 is encoded by the gene GNA14. * Gα15 is encoded by the gene GNA15. Function The general function of Gq is to activate intracellular signaling p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G Protein–coupled Receptor
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 group of evolutionarily-related proteins that are cell surface receptors that detect molecules outside the cell and activate cellular responses. Coupling with G proteins, they are called seven-transmembrane receptors because they pass through the cell membrane seven times. Text was copied from this source, which is available under Attribution 2.5 Generic (CC BY 2.5) license. Ligands can bind either to extracellular N-terminus and loops (e.g. glutamate receptors) or to the binding site within transmembrane helices (Rhodopsin-like family). They are all activated by agonists although a spontaneous auto-activation of an empty receptor can also be observed. G protein-coupled receptors are found only in eukaryotes, including yeast, choanoflagellates, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspartic Acid
Aspartic acid (symbol Asp or D; the ionic form is known as aspartate), is an α-amino acid that is used in the biosynthesis of proteins. Like all other amino acids, it contains an amino group and a carboxylic acid. Its α-amino group is in the protonated –NH form under physiological conditions, while its α-carboxylic acid group is deprotonated −COO− under physiological conditions. Aspartic acid has an acidic side chain (CH2COOH) which reacts with other amino acids, enzymes and proteins in the body. Under physiological conditions (pH 7.4) in proteins the side chain usually occurs as the negatively charged aspartate form, −COO−. It is a non-essential amino acid in humans, meaning the body can synthesize it as needed. It is encoded by the codons GAU and GAC. D-Aspartate is one of two D-amino acids commonly found in mammals. .html" ;"title="/sup>">/sup> In proteins aspartate sidechains are often hydrogen bonded to form asx turns or asx motifs, which frequently occur at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutamic Acid
Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can synthesize enough for its use. It is also the most abundant excitatory neurotransmitter in the vertebrate nervous system. It serves as the precursor for the synthesis of the inhibitory gamma-aminobutyric acid (GABA) in GABA-ergic neurons. Its molecular formula is . Glutamic acid exists in three optically isomeric forms; the dextrorotatory -form is usually obtained by hydrolysis of gluten or from the waste waters of beet-sugar manufacture or by fermentation.Webster's Third New International Dictionary of the English Language Unabridged, Third Edition, 1971. Its molecular structure could be idealized as HOOC−CH()−()2−COOH, with two carboxyl groups −COOH and one amino group −. However, in the solid state and mildly acidic water solutio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-terminus
The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the amine group is bonded to the carboxylic group of another amino acid, making it a chain. That leaves a free carboxylic group at one end of the peptide, called the C-terminus, and a free amine group on the other end called the N-terminus. By convention, peptide sequences are written N-terminus to C-terminus, left to right (in LTR writing systems). This correlates the translation direction to the text direction, because when a protein is translated from messenger RNA, it is created from the N-terminus to the C-terminus, as amino acids are added to the carboxyl end of the protein. Chemistry Each amino acid has an amine group and a carboxylic group. Amino acids link to one another by peptide bonds which form through a dehydration reaction that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
