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Hsp90 facilitates accurate loading of precursor piRNAs into PIWI proteins.

ABSTRACT: PIWI-interacting RNAs (piRNAs) defend the genome against transposon activity in animal gonads. The Hsp90 chaperone machinery has been implicated in the piRNA pathway, but its exact role remains obscure. Here, we examined the effect of 17-N-allylamino-17-demethoxygeldanamycin (17-AAG), an Hsp90-specific inhibitor, on the piRNA pathway. In the silkworm ovary-derived BmN4 cells, 17-AAG treatment reduced the level of piRNAs and PIWI proteins. In vitro, the 5'-nucleotide preference upon precursor piRNA loading was compromised by 17-AAG, whereas 3'-end trimming and 2'-O-methylation were unaffected. Our data highlight a role of Hsp90 in accurate loading of precursor piRNAs into PIWI proteins.

SUBMITTER: Izumi N

PROVIDER: S-EPMC3683924 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Hsp90 facilitates accurate loading of precursor piRNAs into PIWI proteins.

Izumi Natsuko N Kawaoka Shinpei S Yasuhara Satoshi S Suzuki Yutaka Y Sugano Sumio S Katsuma Susumu S Tomari Yukihide Y

RNA (New York, N.Y.) 20130516 7

PIWI-interacting RNAs (piRNAs) defend the genome against transposon activity in animal gonads. The Hsp90 chaperone machinery has been implicated in the piRNA pathway, but its exact role remains obscure. Here, we examined the effect of 17-N-allylamino-17-demethoxygeldanamycin (17-AAG), an Hsp90-specific inhibitor, on the piRNA pathway. In the silkworm ovary-derived BmN4 cells, 17-AAG treatment reduced the level of piRNAs and PIWI proteins. In vitro, the 5'-nucleotide preference upon precursor piR ...[more]

PMID: 23681506

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