Function
Methyltransferase that adds a 2'-O-methyl group at the 3'-end of PIWI-interacting RNAs (piRNAs) and small interfering RNAs (siRNAs) which are classes of regulatory RNAs that are involved in gene silencing in endogenous RNA interference (RNAi) pathways (PubMed:22536158, PubMed:22548001, PubMed:22829772). Methylation protects the 3'-end of small RNAs from tailing and trimming and could constitute a recognition signal for appropriate argonaute machineries (Probable). Methylates and stabilizes 26G-siRNAs (a class of 26 nucleotide siRNAs that possess a monophosphorylated guanine residue at the 5'-end) when they are bound by argonaute protein ergo-1 (PubMed:22536158, PubMed:22548001, PubMed:22829772). This occurs in the female germline and embryo, but not in the male germline (PubMed:22548001). Does not methylate 26G-siRNAs bound by argonaute proteins alg-3 or alg-4 (PubMed:22548001, PubMed:22829772). Methylates and stabilizes 21U-piRNAs, which are a class of 21 nucleotide piRNAs that possess a uracil residue at the 5'-end, in the male and female germline (PubMed:22536158, PubMed:22548001, PubMed:22829772). In addition, may play a role in exogenous RNAi (exoRNAi) pathways in the germline (PubMed:22829772).
Sequence
MAHTSDGWGAPYDNQTYVEAYEQLEIALLEPLDRILETANVEEFRPKFKNHQDPNDRKNKKNNDEEWRDSIYNIATDESDTDDHEQRKNFFQPPLQVQRNSFVKNTLMEFKRSSQIDISRLAVMGCGEMSLEKGICEYLGSFGTINVLSVDIDEPSLSIGQQLLGKHLERNAEILAVETGLPVLMRSYVGDILEPDHRFADVDAIVSMEVVEHIPLPNAKKFVENVLGTLMPRIFIFSTPNHEYNAVFGMEPGEFRHGDHKFEMNRKEFSNWLEELSIRFPHYQIDPPHYIGMTRGYENLSGASQAAVCRLQVDLNTTLPQEVTPYEMVGHLPCRLGSRLIAYNLVKEAFLDWLEKIELQEHEPRTDGYSPYWIFNVQNILHHLKAPVSFALTIDEKVAIKYIQGMTSRKVHAEYSHGFNGIVILQMHSKEELIKTVQDNTL