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Title: The ribosome: A hot spot for the identification of new types of protein methyltransferases
Cellular physiology depends on the alteration of protein structures by covalent modification reactions. Using a combination of bioinformatic, genetic, biochemical, and mass spectrometric approaches, it has been possible to probe ribosomal proteins from the yeast Saccharomyces cerevisiae for posttranslationally methylated amino acid residues and for the enzymes that catalyze these modifications. These efforts have resulted in the identification and characterization of the first protein histidine methyltransferase, the first N-terminal protein methyltransferase, two unusual types of protein arginine methyltransferases, and a new type of cysteine methylation. Two of these enzymes may modify their substrates during ribosomal assembly because the final methylated histidine and arginine residues are buried deep within the ribosome with contacts only with RNA. Two of these modifications occur broadly in eukaryotes, including humans, while the others demonstrate a more limited phylogenetic range. Analysis of strains where the methyltransferase genes are deleted has given insight into the physiological roles of these modifications. These reactions described here add diversity to the modifications that generate the typical methylated lysine and arginine residues previously described in histones and other proteins.  more » « less
Award ID(s):
1714569
PAR ID:
10058221
Author(s) / Creator(s):
Date Published:
Journal Name:
Journal of Biological Chemistry
ISSN:
0021-9258
Page Range / eLocation ID:
jbc.AW118.003235
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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