Protein Summary

RsmA from Saccharomyces cerevisiae

Full name: Dimethyladenosine transferase
Synonym: Dim1
GI: 1169344
Orf: YPL266W
COG: COG0030
UniProt: P41819
Enzyme type: methyltransferase
Position of modification - modification: s:1779(1518) - m6,6A
s:1780(1519) - m6,6A


SceRsmA (formerly Dim1p) dimethylates two adjacent A (positions 1779 and 1780; 1518 and 1519 in E. coli numberings) in the loop of a conserved hairpin h45 near the 3′-end of 18S rRNA. AdoMet is the methyl group donor. RsmA can bind on naked rRNA but the target bases cannot be methylated before a subset of ribosomal proteins have bound. Dim2p could be a cofactor. Bacterial RsmA (KsgA) is the ortholog of yeast RsmA (Dim1p). They belong to the erm family of methyltransferases responsible for erythromycin resistance. RsmA homologs exists also Archaea. Notice, the acronym RsmA has also been used for for Regulator of Secondary Metabolism A, a protein not related to the RNA small subunit Methyltransferase.

Protein sequence:


Enzymatic activities

Reaction Substrate Type Position
A:m6A rRNA (r) SSU/18S/cytosolic 1779
m6A:m6,6A rRNA (r) SSU/18S/cytosolic 1779
A:m6A rRNA (r) SSU/18S/cytosolic 1780
m6A:m6,6A rRNA (r) SSU/18S/cytosolic 1780


Title Authors Journal Details PubMed Id DOI
Recognition of a complex substrate by the KsgA/Dim1 family of enzymes has been conserved throughout evolution. O'Farrell HC, Pulicherla N, Desai PM, Rife JP RNA [details] 16540698 -
Structural and functional divergence within the Dim1/KsgA family of rRNA methyltransferases. Pulicherla N, Pogorzala LA, Xu Z, O Farrell HC, Musayev FN, Scarsdale JN, Sia EA, Culver GM, Rife JP J Mol Biol [details] 19520088 -
The DIM1 gene responsible for the conserved m6(2)Am6(2)A dimethylation in the 3'-terminal loop of 18 S rRNA is essential in yeast. Lafontaine D, Delcour J, Glasser AL, Desgres J, Vandenhaute J J Mol Biol [details] 8064863 -
Comprehensive phylogenetic analysis of evolutionarily conserved rRNA adenine dimethyltransferase suggests diverse bacterial contributions to the nucleus-encoded plastid proteome. Park AK, Kim H, Jin HJ Mol Phylogenet Evol [details] 19017544 -
Dim2p, a KH-domain protein required for small ribosomal subunit synthesis. Vanrobays E, Gelugne JP, Caizergues-Ferrer M, Lafontaine DL RNA [details] 15037774 -
Yeast 18S rRNA dimethylase Dim1p: a quality control mechanism in ribosome synthesis? Lafontaine DL, Preiss T, Tollervey D Mol Cell Biol [details] 9528805 -

Last modification of this entry: 2012-07-04 12:43:59.050018
Edited by a user: magda
Edited content: Changed if_enzyme, nomenclature, catalytic_domain_fold and comments.