SMN:SM protein complex SMN complex Loading and methylation of Sm proteins onto SMN Complexes Authored: Gillespie, ME, 2007-01-29 20:29:54 GENE ONTOLOGYGO:0000387 Pubmed10601333 Pubmed10725331 Pubmed10747894 Pubmed10851237 Pubmed11714716 Pubmed11715014 Pubmed11720283 Pubmed11748230 Pubmed12065586 Pubmed9323129 Pubmed9323130 Reactome Database ID Release 43191790 Reactome, http://www.reactome.org ReactomeREACT_10041 Reviewed: Luhrmann, R, 2007-04-30 18:31:22 The survival of motor neurons (SMN) complex binds to Sm proteins and small nuclear RNAs (snRNAs) in the cytoplasm. Sm is part the SMN multiprotein complex that contains Gemins 2 – 7, including the DEAD-box RNA helicase Gemin3. The binding of the SMN complex to the snRNAs depends on the presence of specific, high-affinity (nanomolar) binding domains in the snRNAs. The SMN complex binds the Sm proteins through the Sm domains interaction with the Gemins, the TUDOR domain, and through unique arginine- and glycine-rich (RG) domains found in three of these, SmB, SmD1 and SmD3. The association with RG domains is strongly enhanced by the post-translational symmetric dimethylation of specific arginines in these domains, a process that is carried out by the methylosome (JBP1 or PRMT5) complex.