User:Bigrocksmall/sandbox
From Wikipedia, the free encyclopedia
Glutamate decarboxylase or glutamic acid decarboxylase (GAD) is an enzyme that catalyzes the decarboxylation of glutamate to GABA and CO2. GAD uses PLP as a cofactor. The reaction proceeds as follows:
- HOOC-CH2-CH2-CH(NH2)-COOH → CO2 + HOOC-CH2-CH2-CH2NH2
Glutamic acid decarboxylase 1 | |||||||
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Identifiers | |||||||
Symbol | GAD1 | ||||||
Alt. symbols | glutamate decarboxylase 1 (brain, 67kD); GAD67 | ||||||
NCBI gene | 2571 | ||||||
HGNC | 4092 | ||||||
OMIM | 605363 | ||||||
RefSeq | NM_000817 | ||||||
UniProt | Q99259 | ||||||
Other data | |||||||
EC number | 4.1.1.15 | ||||||
Locus | Chr. 2 q31 | ||||||
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glutamic acid decarboxylase 2 | |||||||
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Identifiers | |||||||
Symbol | GAD2 | ||||||
Alt. symbols | GAD65 | ||||||
NCBI gene | 2572 | ||||||
HGNC | 11284 | ||||||
OMIM | 4093 | ||||||
RefSeq | NM_001047 | ||||||
UniProt | Q05329 | ||||||
Other data | |||||||
EC number | 4.1.1.15 | ||||||
Locus | Chr. 10 p11.23 | ||||||
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In mammals, GAD exists in two isoforms with molecular weights of 67 and 65 kDa (GAD67 and GAD65), and although they share more than 70% of sequence similarity, they are encoded by two different genes on different chromosomes (GAD1 and GAD2 genes, chromosomes 4 and 10 respectively).[1][2] GAD67 and GAD65 are expressed in the brain where GABA is used as a neurotransmitter, and they are also expressed in the insulin-producing β-cells of the pancreas, in varying ratios depending upon the species.[3] Together, these two enzymes maintain the only physiological supply of GABA in mammals.[2]
Several truncated transcripts and polypeptides of GAD67 are detectable in the developing brain,[4] however their function, if any, is unknown.