How does the royal family of Tudor rule the PIWI-interacting RNA pathway?
PIWI (P-element-induced wimpy testis) proteins are a subset of the Argonaute proteins and are expressed predominantly in the germlines of a variety of organisms, including Drosophila and mammals. PIWI proteins associate specifically with PIWI-interacting RNAs (piRNAs), small RNAs that are also expressed predominantly in germlines, and silence transposable DNA elements and other genes showing complementarities to the sequences of associated piRNAs. This mechanism helps to maintain the integrity of the genome and the development of gametes. PIWI proteins have been shown recently to contain symmetrical dimethyl arginines (sDMAs), and this modification is mediated by the methyltransferase PRMT5 (also known as Dart5 or Capsuleen). It was then demonstrated that multiple members of the Tudor (Tud) family of proteins, which are necessary for gametogenesis in both flies and mice, associate with PIWI proteins specifically through sDMAs in various but particular combinations. Although Tud domains in Tud family members are known to be sDMA-binding modules, involvement of the Tudor family at the molecular level in the piRNA pathway has only recently come into focus.
Siomi
Mikiko C
MC
Keio University School of Medicine, Tokyo 160-8582, Japan. siomim@sc.itc.keio.ac.jp
Mannen
Taro
T
Siomi
Haruhiko
H
D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000378:metabolism; D060565:Argonaute Proteins; D029721:Drosophila Proteins / Q000378:metabolism; D006801:Humans; D026901:Membrane Transport Proteins / Q000378:metabolism*; D011496:Protein Methyltransferases / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D011506:Proteins / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism*; D034743:RNA-Induced Silencing Complex / Q000378:metabolism
D060565:Argonaute Proteins; D029721:Drosophila Proteins; D026901:Membrane Transport Proteins; D011506:Proteins; D034741:RNA, Small Interfering; D034743:RNA-Induced Silencing Complex; C116498:piwi protein, Drosophila; C024917:symmetric dimethylarginine; D001120:Arginine; D011496:Protein Methyltransferases