title: 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.
authors.affiliation: Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
authors.forename: Natsuko
authors.initials: N
authors.lastname: Izumi
authors.forename: Shinpei
authors.initials: S
authors.lastname: Kawaoka
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yasuhara
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Sumio
authors.initials: S
authors.lastname: Sugano
authors.forename: Susumu
authors.initials: S
authors.lastname: Katsuma
authors.forename: Yukihide
authors.initials: Y
authors.lastname: Tomari
mesh_terms: D000818:Animals; D060565:Argonaute Proteins / Q000235:genetics / Q000378:metabolism*; D016227:Benzoquinones / Q000494:pharmacology; D012831:Bombyx / Q000166:cytology; D002460:Cell Line; D005260:Female; D005786:Gene Expression Regulation; D018841:HSP90 Heat-Shock Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D047468:Immunoprecipitation; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D047029:Lactams, Macrocyclic / Q000494:pharmacology; D008745:Methylation; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism; D010053:Ovary / Q000166:cytology; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism*
chemical_list: D060565:Argonaute Proteins; D016227:Benzoquinones; D018841:HSP90 Heat-Shock Proteins; D019476:Insect Proteins; D047029:Lactams, Macrocyclic; D035683:MicroRNAs; D034741:RNA, Small Interfering; C112765:tanespimycin
keywords: Hsp90; PIWI; PIWI-interacting RNAs; chaperone; piRNAs