Download MendeleyStructure and catalytic mechanism of a SET domain protein methyltransferase.
Trievel, R.C., Beach, B.M., Dirk, L.M., Houtz, R.L., Hurley, J.H.(2002) Cell 111: 91-103
- PubMed: 12372303
- DOI: https://doi.org/10.1016/s0092-8674(02)01000-0
- Primary Citation of Related Structures:
1MLV - PubMed Abstract:
Protein lysine methylation by SET domain enzymes regulates chromatin structure, gene silencing, transcriptional activation, plant metabolism, and other processes. The 2.6 A resolution structure of Rubisco large subunit methyltransferase in a pseudo-bisubstrate complex with S-adenosylhomocysteine and a HEPES ion reveals an all-beta architecture for the SET domain embedded within a larger alpha-helical enzyme fold. Conserved regions of the SET domain bind S-adenosylmethionine and substrate lysine at two sites connected by a pore. We propose that methyl transfer is catalyzed by a conserved Tyr at a narrow pore connecting the sites. The cofactor enters by a "back door" on the opposite side of the enzyme from substrate, promoting highly specific protein recognition and allowing addition of multiple methyl groups.
Organizational Affiliation:
Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
