|ZFIN ID: ZDB-PUB-101004-33|
Hen1 is required for oocyte development and piRNA stability in zebrafish
Kamminga, L.M., Luteijn, M.J., den Broeder, M.J., Redl, S., Kaaij, L.J., Roovers, E.F., Ladurner, P., Berezikov, E., and Ketting, R.F.
|Source:||The EMBO journal 29(21): 3688-3700 (Journal)|
|Registered Authors:||den Broeder, Marjo, Kamminga, Leonie, Ketting, René|
|Keywords:||germ line, Hen1, piRNA, Piwi, zebrafish|
|PubMed:||20859253 Full text @ EMBO J.|
Kamminga, L.M., Luteijn, M.J., den Broeder, M.J., Redl, S., Kaaij, L.J., Roovers, E.F., Ladurner, P., Berezikov, E., and Ketting, R.F. (2010) Hen1 is required for oocyte development and piRNA stability in zebrafish. The EMBO journal. 29(21):3688-3700.
ABSTRACTPiwi-interacting RNAs (piRNAs) are germ line-specific small RNA molecules that have a function in genome defence and germ cell development. They associate with a specific class of Argonaute proteins, named Piwi, and function through an RNA interference-like mechanism. piRNAs carry a 2'-O-methyl modification at their 3' end, which is added by the Hen1 enzyme. We show that zebrafish hen1 is specifically expressed in germ cells and is essential for maintaining a female germ line, whereas it is dispensable in the testis. Hen1 protein localizes to nuage through its C-terminal domain, but is not required for nuage formation. In hen1 mutant testes, piRNAs become uridylated and adenylated. Uridylation frequency is highest on retro-transposon-derived piRNAs and is accompanied by decreased piRNA levels and mild derepression of transposon transcripts. Altogether, our data suggest the existence of a uridylation-mediated 3'-5' exonuclease activity acting on piRNAs in zebrafish germ cells, which is counteracted by nuage-bound Hen1 protein. This system discriminates between piRNA targets and is required for ovary development and fully efficient transposon silencing.