Methionine Adenosyltransferase I Alpha (MAT1a)

MAT; SAMS; MATA1; SAMS1; AMS1; S-Adenosylmethionine Synthetase; S-adenosylmethionine synthase isoform type-1

SPN	Q339
HGNC	6903
MGI	88017
PubMed	18167064
RGD	3050
UniProt	Q00266

MAT1a catalyzes a two-step reaction that involves the transfer of the adenosyl moiety of ATP to methionine to form S-adenosylmethionine and tripolyphosphate, which is subsequently cleaved to PPi and Pi. S-adenosylmethionine is the source of methyl groups for most biological methylations. The encoded protein is found as a homotetramer (MAT I) or a homodimer (MAT III) whereas a third form, MAT II (gamma), is encoded by the MAT2A gene. Mutations in this gene are associated with methionine adenosyltransferase deficiency.

The peptide maps of the 2 forms were possibly identical, although they showed different specific activities at physiologic concentrations of methionine. The findings suggested that the 2 isoforms are encoded by the same gene.

Reference

"Characterization of a full-length cDNA encoding human liver S-adenosylmethionine synthetase: tissue-specific gene expression and mRNA levels in hepatopathies."
Biochem. J. 293:481-486(1993) [PubMed] [Europe PMC] [Abstract]

"Molecular cloning and nucleotide sequence of cDNA encoding the human liver S-adenosylmethionine synthetase."
Biochem. Int. 25:81-90(1991) [PubMed] [Europe PMC] [Abstract]

"The DNA sequence and comparative analysis of human chromosome 10."
Nature 429:375-381(2004) [PubMed] [Europe PMC] [Abstract]

"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]

"Initial characterization of the human central proteome."
BMC Syst. Biol. 5:17-17(2011) [PubMed] [Europe PMC] [Abstract]

"An enzyme assisted RP-RPLC approach for in-depth analysis of human liver phosphoproteome."
J. Proteomics 96:253-262(2014) [PubMed] [Europe PMC] [Abstract]

"Crystal structure of the human s-adenosylmethionine synthetase 1 in complex with the product."
Submitted (JUL-2007) to the PDB data bank

"Molecular mechanisms of an inborn error of methionine pathway. Methionine adenosyltransferase deficiency."
J. Clin. Invest. 96:1943-1947(1995) [PubMed] [Europe PMC] [Abstract]

"Demyelination of the brain is associated with methionine adenosyltransferase I/III deficiency."
J. Clin. Invest. 98:1021-1027(1996) [PubMed] [Europe PMC] [Abstract]

"Dominant inheritance of isolated hypermethioninemia is associated with a mutation in the human methionine adenosyltransferase 1A gene."
Am. J. Hum. Genet. 60:540-546(1997) [PubMed] [Europe PMC] [Abstract]

"Methionine adenosyltransferase I/III deficiency: novel mutations and clinical variations."
Am. J. Hum. Genet. 66:347-355(2000) [PubMed] [Europe PMC] [Abstract]