Hen1 is required for oocyte development and piRNA stability in zebrafish
Hen1 is required for oocyte development and piRNA stability in zebrafish
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DOI：
10.1038/emboj.2010.233
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发表时间：
2010-11-03
期刊：
影响因子：
11.4
通讯作者：
Ketting, Rene F.
中科院分区：
文献类型：
--
作者：
Kamminga, Leonie M.;Luteijn, Maartje J.;Ketting, Rene F.
Piwi相互作用RNA(PiRNAs)是一种生殖系特异的小RNA分子，在基因组防御和生殖细胞发育中具有功能。它们与一类特定的名为Piwi的ArgAerte蛋白质结合，并通过类似RNA干扰的机制发挥作用。PiRNAs在其3‘端带有2’-O-甲基修饰，该修饰由Hen1酶添加。我们发现斑马鱼HeN1在生殖细胞中特异表达，对维持雌性生殖系是必不可少的，而在睾丸中它是必不可少的。Hen1蛋白通过其C-末端结构域定位于Nuage，但不是Nuage形成所必需的。在hen1突变的睾丸中，piRNAs尿苷化和腺苷化。逆转座子衍生的piRNAs的尿酸分泌频率最高，并伴随着piRNA水平的降低和转座子转录产物的轻度去抑制。总之，我们的数据表明斑马鱼生殖细胞中存在尿苷基化介导的3‘-5’核酸外切酶活性作用于piRNAs，该活性可被Nuage结合的Hen1蛋白所抵消。该系统能区分不同的piRNA靶标，是卵巢发育和完全有效的转座子沉默所必需的。EMBO期刊(2010)29,3688-3700。DOI：10.1038/Intemj.2010.233；2010年9月21日在线发布
Piwi-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. The EMBO Journal (2010) 29, 3688-3700. doi:10.1038/emboj.2010.233; Published online 21 September 2010