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MAO-A
Monoamine oxidase A, also known as MAO-A, is an enzyme ( E.C. 1.4.3.4) that in humans is encoded by the ''MAOA'' gene. This gene is one of two neighboring gene family members that encode mitochondrial enzymes which catalyze the oxidative deamination of amines, such as norepinephrine, serotonin and tyramine. A mutation of this gene results in Brunner syndrome. This gene has also been associated with a variety of other psychiatric disorders, including antisocial behavior. Alternatively spliced transcript variants encoding multiple isoforms have been observed. Structures Gene Monoamine oxidase A, also known as MAO-A, is an enzyme that in humans is encoded by the ''MAOA'' gene. The promoter of ''MAOA'' contains conserved binding sites for Sp1, GATA2, and TBP. This gene is adjacent to a related gene ('' MAOB'') on the opposite strand of the X chromosome. In humans, there is a 30-base repeat sequence repeated several different numbers of times in the promoter region of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MAOA Gene With ChrX Ideogram
Monoamine oxidase A, also known as MAO-A, is an enzyme (Enzyme classification, E.C. 1.4.3.4) that in humans is encoded by the ''MAOA'' gene. This gene is one of two neighboring gene family members that encode mitochondrial enzymes which catalyze the oxidative deamination of amines, such as norepinephrine, serotonin and tyramine. A mutation of this gene results in Brunner syndrome. This gene has also been associated with a variety of other psychiatric disorders, including Anti-social behavior, antisocial behavior. Alternatively spliced transcript variants encoding multiple isoforms have been observed. Structures Gene Monoamine oxidase A, also known as MAO-A, is an enzyme that in humans is encoded by the ''MAOA'' gene. The promoter of ''MAOA'' contains conserved binding sites for Sp1 transcription factor, Sp1, GATA2, and TATA Binding Protein, TBP. This gene is adjacent to a related gene (''MAOB'') on the opposite strand of the X chromosome. In humans, there is a 30-base Vari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoamine Oxidase
Monoamine oxidases (MAO) () are a family of enzymes that catalyze the oxidation of monoamines, employing oxygen to clip off their amine group. They are found bound to the outer membrane of mitochondria in most cell types of the body. The first such enzyme was discovered in 1928 by Mary Bernheim in the liver and was named tyramine oxidase. The MAOs belong to the protein family of flavin-containing amine oxidoreductases. MAOs are important in the breakdown of monoamines ingested in food, and also serve to inactivate monoamine neurotransmitters. Because of the latter, they are involved in a number of psychiatric and neurological diseases, some of which can be treated with monoamine oxidase inhibitors (MAOIs) which block the action of MAOs. Subtypes and tissue distribution In humans there are two types of MAO: MAO-A and MAO-B. * Both are found in neurons and astroglia. * Outside the central nervous system: ** MAO-A is also found in the liver, pulmonary vascular end ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MAOB
Monoamine oxidase B (MAO-B) is an enzyme that in humans is encoded by the ''MAOB'' gene. The protein encoded by this gene belongs to the flavin monoamine oxidase family. It is an enzyme located in the outer mitochondrial membrane. It catalyzes the oxidative deamination of biogenic and xenobiotic amines and plays an important role in the catabolism of neuroactive and vasoactive amines in the central nervous system and peripheral tissues. This protein preferentially degrades benzylamine and phenethylamine. Similar to monoamine oxidase A (MAO-A), MAO-B is also involved in the catabolism of dopamine. Structure and function MAO-B has a hydrophobic bipartite elongated cavity that (for the "open" conformation) occupies a combined volume close to 700 Å3. hMAO-A has a single cavity that exhibits a rounder shape and is larger in volume than the "substrate cavity" of hMAO-B. The first cavity of hMAO-B has been termed the ''entrance cavity'' (290 Å3), the second ''substrate cavity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brunner Syndrome
Brunner syndrome is a rare genetic disorder associated with a mutation in the MAOA gene. It is characterized by lower than average IQ (typically about 85), problematic impulsive behavior (such as pyromania, hypersexuality and violence), sleep disorders and mood swings. It was identified in fourteen males from one family in 1993. It has since been discovered in additional families. Signs and symptoms The following signs and symptoms occur in people with monoamine oxidase A deficiency, which causes Brunner syndrome: * lack of impulse control * aggressive or violent outbursts * ASD or ADHD-like behavioral features ** obsessive behaviors ** difficulties forming friendships ** problems focusing attention * sleep problems ** trouble falling asleep ** night terrors * skin flushing * sweating * headaches * diarrhea Causes Brunner syndrome is caused by a monoamine oxidase A (MAOA) deficiency, which leads to an excess of monoamines in the brain, such as serotonin, dopamine, and nore ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic compound, organic chemical in the catecholamine family that functions in the brain and human body, body as a hormone, neurotransmitter and neuromodulator. The name "noradrenaline" (from Latin '':wikt:ad-, ad'', "near", and '':wikt:ren, ren'', "kidney") is more commonly used in the United Kingdom and the rest of the world, whereas "norepinephrine" (from Ancient Greek :wikt:ἐπί, ἐπῐ́ (''epí''), "upon", and :wikt:νεφρός, νεφρός (''nephrós''), "kidney") is usually preferred in the United States. "Norepinephrine" is also the international nonproprietary name given to norepinephrine (drug), the drug. Regardless of which name is used for the substance itself, parts of the body that produce or are affected by it are referred to as noradrenergic. The general function of norepinephrine is to mobilize the brain and body for action. Norepinephrine release is lowest during sleep, rise ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyramine
Tyramine ( ) (also spelled tyramin), also known under several other names, is a naturally occurring trace amine derived from the amino acid tyrosine. Tyramine acts as a catecholamine releasing agent. Notably, it is unable to cross the blood-brain barrier, resulting in only non-psychoactive peripheral sympathomimetic effects following ingestion. A hypertensive crisis can result, however, from ingestion of tyramine-rich foods in conjunction with the use of monoamine oxidase inhibitors (MAOIs). Occurrence Tyramine occurs widely in plants and animals, and is metabolized by various enzymes, including monoamine oxidases. In foods, it often is produced by the decarboxylation of tyrosine during fermentation or decay. Foods that are fermented, cured, pickled, aged, or spoiled have high amounts of tyramine. Tyramine levels go up when foods are at room temperature or go past their freshness date. Specific foods containing considerable amounts of tyramine include: * Strong ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X Chromosome
The X chromosome is one of the two sex chromosomes in many organisms, including mammals, and is found in both males and females. It is a part of the XY sex-determination system and XO sex-determination system. The X chromosome was named for its unique properties by early researchers, which resulted in the naming of its counterpart Y chromosome, for the next letter in the alphabet, following its subsequent discovery. Discovery It was first noted that the X chromosome was special in 1890 by Hermann Henking in Leipzig. Henking was studying the testicles of '' Pyrrhocoris'' and noticed that one chromosome did not take part in meiosis. Chromosomes are so named because of their ability to take up staining (''chroma'' in Greek means ''color''). Although the X chromosome could be stained just as well as the others, Henking was unsure whether it was a different class of the object and consequently named it ''X element'', which later became X chromosome after it was established that it w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme Classification
The Enzyme Commission number (EC number) is a numerical classification scheme for enzymes, based on the chemical reactions they catalyze. As a system of enzyme nomenclature, every EC number is associated with a recommended name for the corresponding enzyme-catalyzed reaction. EC numbers do not specify enzymes but enzyme-catalyzed reactions. If different enzymes (for instance from different organisms) catalyze the same reaction, then they receive the same EC number. Furthermore, through convergent evolution, completely different protein folds can catalyze an identical reaction (these are sometimes called non-homologous isofunctional enzymes) and therefore would be assigned the same EC number. By contrast, UniProt identifiers uniquely specify a protein by its amino acid sequence. Format of number Every enzyme code consists of the letters "EC" followed by four numbers separated by periods. Those numbers represent a progressively finer classification of the enzyme. Preliminary E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TATA Binding Protein
The TATA-binding protein (TBP) is a general transcription factor that binds to a DNA sequence called the TATA box. This DNA sequence is found about 30 base pairs upstream of the transcription start site in some eukaryotic gene promoters. TBP gene family TBP is a member of a small gene family of TBP-related factors. The first TBP-related factor (TRF/TRF1) was identified in the fruit fly Drosophila, but appears to be fly or insect-specific. Subsequently TBPL1/TRF2 was found in the genomes of many metazoans, whereas vertebrate genomes encode a third vertebrate family member, TBPL2/TRF3. In specific cell types or on specific promoters TBP can be replaced by one of these TBP-related factors, some of which interact with the TATA box similarly to TBP. Role as transcription factor TBP is a subunit of the eukaryotic general transcription factor TFIID. TFIID is the first protein to bind to DNA during the formation of the transcription preinitiation complex of RNA polymerase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C-terminal
The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, carboxy tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is translated from messenger RNA, it is created from N-terminus to C-terminus. The convention for writing peptide sequences is to put the C-terminal end on the right and write the sequence from N- to C-terminus. Chemistry Each amino acid has a carboxyl group and an amine group. Amino acids link to one another to form a chain by a dehydration reaction which joins the amine group of one amino acid to the carboxyl group of the next. Thus polypeptide chains have an end with an unbound carboxyl group, the C-terminus, and an end with an unbound amine group, the N-terminus. Proteins are naturally synthesized starting from the N-terminus and ending at the C-terminus. Function C-terminal retention signals While the N-terminus of a prote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flavin Adenine Dinucleotide
In biochemistry, flavin adenine dinucleotide (FAD) is a redox-active coenzyme associated with various proteins, which is involved with several enzymatic reactions in metabolism. A flavoprotein is a protein that contains a flavin group, which may be in the form of FAD or flavin mononucleotide (FMN). Many flavoproteins are known: components of the succinate dehydrogenase complex, α-ketoglutarate dehydrogenase, and a component of the pyruvate dehydrogenase complex. FAD can exist in four redox states, which are the flavin-N(5)-oxide, quinone, semiquinone, and hydroquinone. FAD is converted between these states by accepting or donating electrons. FAD, in its fully oxidized form, or quinone form, accepts two electrons and two protons to become FADH2 (hydroquinone form). The semiquinone (FADH·) can be formed by either reduction of FAD or oxidation of FADH2 by accepting or donating one electron and one proton, respectively. Some proteins, however, generate and maintain a super ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Domain
In molecular biology, a protein domain is a region of a protein's Peptide, polypeptide chain that is self-stabilizing and that Protein folding, folds independently from the rest. Each domain forms a compact folded Protein tertiary structure, three-dimensional structure. Many proteins consist of several domains, and a domain may appear in a variety of different proteins. Molecular evolution uses domains as building blocks and these may be recombined in different arrangements to create proteins with different functions. In general, domains vary in length from between about 50 amino acids up to 250 amino acids in length. The shortest domains, such as zinc fingers, are stabilized by metal ions or Disulfide bond, disulfide bridges. Domains often form functional units, such as the calcium-binding EF-hand, EF hand domain of calmodulin. Because they are independently stable, domains can be "swapped" by genetic engineering between one protein and another to make chimera (protein), chimeric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
