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MVH in piRNA processing and gene silencing of retrotransposons.

ABSTRACT: VASA is an evolutionarily conserved RNA helicase essential for germ cell development. The mouse PIWI family proteins MILI and MIWI2 are involved in production of Piwi-interacting RNAs (piRNAs) in fetal male germ cells through a ping-pong amplification cycle. Expression of retrotransposons is elevated in MILI- and MIWI2-deficient male germ cells due to defective de novo DNA methylation, which is presumably caused by impaired piRNA expression. Here, we report that essentially the same abnormalities are observed in MVH (mouse VASA homolog)-deficient mice. Comprehensive analysis of piRNAs in MVH-deficient fetal male germ cells showed that MVH plays crucial roles in the early phase of the ping-pong amplification cycle.

SUBMITTER: Kuramochi-Miyagawa S

PROVIDER: S-EPMC2861188 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

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MVH in piRNA processing and gene silencing of retrotransposons.

Kuramochi-Miyagawa Satomi S Watanabe Toshiaki T Gotoh Kengo K Takamatsu Kana K Chuma Shinichiro S Kojima-Kita Kanako K Shiromoto Yusuke Y Asada Noriko N Toyoda Atsushi A Fujiyama Asao A Totoki Yasushi Y Shibata Tatsuhiro T Kimura Tohru T Nakatsuji Norio N Noce Toshiaki T Sasaki Hiroyuki H Nakano Toru T

Genes & development 20100501 9

VASA is an evolutionarily conserved RNA helicase essential for germ cell development. The mouse PIWI family proteins MILI and MIWI2 are involved in production of Piwi-interacting RNAs (piRNAs) in fetal male germ cells through a ping-pong amplification cycle. Expression of retrotransposons is elevated in MILI- and MIWI2-deficient male germ cells due to defective de novo DNA methylation, which is presumably caused by impaired piRNA expression. Here, we report that essentially the same abnormalitie ...[more]

PMID: 20439430

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