Methionine adenosyltransferase 2 subunit beta (MAT2B)

Methionine adenosyltransferase 2 subunit beta (MAT2B) is a regulatory, non-catalytic subunit of the methionine adenosyltransferase (MAT) enzyme complex, which catalyzes the biosynthesis of S-adenosylmethionine (SAMe) from methionine and ATP[1][2][3][4]. MAT2B, encoded by the MAT2B gene, forms a complex with the catalytic subunit MAT2A, together regulating the cellular levels and flux of SAMe, the principal methyl donor required for methylation of DNA, histones, and other proteins[1][2][4]. MAT2B belongs to the short-chain dehydrogenase/reductase (SDR) superfamily, possesses NADP(H) binding capacity, and exists as at least two alternatively spliced isoforms with tissue- and context-specific functions[3]. Expression of MAT2B and its catalytic partner MAT2A are upregulated in various cancers (e.g., hepatocellular carcinoma and colon cancer), implicating the MATα2β complex in tumor progression and making it a focus of pharmacological interest for cancer therapy and methylation disorders[1][2][4]. MAT2B interacts with a range of nuclear and cytoplasmic proteins and is crucial for sustaining the epigenetic and signaling environments characteristic of rapidly proliferating cells[1][3]. Resveratrol and NADP can bind MAT2B in vitro, providing structural insights for possible future drug development[3].

Other names

Methionine adenosyltransferase 2 non-catalytic beta subunitMAT2BTGRMSTP045Nbla02999UNQ2435/PRO4995MAT II betaMATIIbetaSDR23E1Methionine adenosyltransferase II betaPutative dTDP-4-keto-6-deoxy-D-glucose 4-reductaseshort chain dehydrogenase/reductase family 23E member 1testicular tissue protein Li 118beta regulatory subunit of methionine adenosyltransferase

Modulates MAT2A catalytic activity and affinity for its substrates (methionine and ATP), increases flux of SAMe required for cellular methylation reactions, influences signaling and epigenetic regulation through methyl donor supply, functions as a regulatory subunit of the MATα2β complex with tissue-specific expression