Arginine methylation of Piwi proteins catalysed by dPRMT5 is required for Ago3 and Aub stability.
Piwi family proteins are essential for germline development and bind piwi-interacting RNAs (piRNAs). The grandchildless gene aub of Drosophila melanogaster encodes the piRNA-binding protein Aubergine (Aub), which is essential for formation of primordial germ cells (PGCs). Here we report that Piwi family proteins of mouse, Xenopus laevis and Drosophila contain symmetrical dimethylarginines (sDMAs). We found that Piwi proteins are expressed in Xenopus oocytes and we identified numerous Xenopus piRNAs. We report that the Drosophila homologue of protein methyltransferase 5 (dPRMT5, csul/dart5), which is also the product of a grandchildless gene, is required for arginine methylation of Drosophila Piwi, Ago3 and Aub proteins in vivo. Loss of dPRMT5 activity led to a reduction in the levels of piRNAs, Ago3 and Aub proteins, and accumulation of retrotransposons in the Drosophila ovary. Our studies explain the relationship between aub and dPRMT5 (csul/dart5) genes by demonstrating that dPRMT5 is the enzyme that methylates Aub. Our findings underscore the significance of sDMA modification of Piwi proteins in the germline and suggest an interacting pathway of genes that are required for piRNA function and PGC specification.
Department of Pathology and Laboratory Medicine, Division of Neuropathology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.
Yohei
Y
Kirino
Namwoo
N
Kim
Mariàngels
M
de Planell-Saguer
Eugene
E
Khandros
Stephanie
S
Chiorean
Peter S
PS
Klein
Isidore
I
Rigoutsos
Thomas A
TA
Jongens
Zissimos
Z
Mourelatos
D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000032:analysis / Q000378:metabolism*; D060565:Argonaute Proteins; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster; D005260:Female; D005854:Germ Cells / Q000378:metabolism; D008297:Male; D008745:Methylation; D051379:Mice; D035683:MicroRNAs / Q000378:metabolism; D009865:Oocytes / Q000378:metabolism; D010053:Ovary / Q000378:metabolism; D010448:Peptide Initiation Factors / Q000737:chemistry / Q000378:metabolism*; D011496:Protein Methyltransferases / Q000235:genetics / Q000378:metabolism*; D011499:Protein Processing, Post-Translational / Q000502:physiology*; D055550:Protein Stability; D011484:Protein-Arginine N-Methyltransferases; D011506:Proteins / Q000737:chemistry / Q000378:metabolism; D034741:RNA, Small Interfering / Q000737:chemistry / Q000378:metabolism; D034743:RNA-Induced Silencing Complex / Q000737:chemistry / Q000378:metabolism*; D018626:Retroelements / Q000235:genetics; D013737:Testis / Q000378:metabolism; D014982:Xenopus laevis
C518392:AGO3 protein, Drosophila; D060565:Argonaute Proteins; D029721:Drosophila Proteins; D035683:MicroRNAs; D010448:Peptide Initiation Factors; C448522:Piwil1 protein, mouse; C448521:Piwil2 protein, mouse; D011506:Proteins; D034741:RNA, Small Interfering; D034743:RNA-Induced Silencing Complex; D018626:Retroelements; C436124:aub protein, Drosophila; C487735:dimethylarginine; C116498:piwi protein, Drosophila; D001120:Arginine; D011496:Protein Methyltransferases; D011484:Protein-Arginine N-Methyltransferases; C512734:csul protein, Drosophila