title: HSP90α plays an important role in piRNA biogenesis and retrotransposon repression in mouse.
abstract: HSP90, found in all kingdoms of life, is a major chaperone protein regulating many client proteins. We demonstrated that HSP90α, one of two paralogs duplicated in vertebrates, plays an important role in the biogenesis of fetal PIWI-interacting RNAs (piRNA), which act against the transposon activities, in mouse male germ cells. The knockout mutation of Hsp90α resulted in a large reduction in the expression of primary and secondary piRNAs and mislocalization of MIWI2, a PIWI homolog. Whereas the mutation in Fkbp6 encoding a co-chaperone reduced piRNAs of 28-32 nucleotides in length, the Hsp90α mutation reduced piRNAs of 24-32 nucleotides, suggesting the presence of both FKBP6-dependent and -independent actions of HSP90α. Although DNA methylation and mRNA levels of L1 retrotransposon were largely unchanged in the Hsp90α mutant testes, the L1-encoded protein was increased, suggesting the presence of post-transcriptional regulation. This study revealed the specialized function of the HSP90α isofom in the piRNA biogenesis and repression of retrotransposons during the development of male germ cells in mammals.
authors.affiliation: Department of Immunology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Kita-ku, Okayama 700-8558, Japan Division of Epigenomics and Development, Medical Institute of Bioregulation, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Ichiyanagi
authors.affiliation: Division of Epigenomics and Development, Medical Institute of Bioregulation, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Ichiyanagi
authors.affiliation: Division of Epigenomics and Development, Medical Institute of Bioregulation, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Ogawa
authors.affiliation: Department of Pathology, Medical School and Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan CREST, Japan Science and Technology Agency (JST), Saitama 332-0012, Japan.
authors.forename: Satomi
authors.initials: S
authors.lastname: Kuramochi-Miyagawa
authors.affiliation: Department of Pathology, Medical School and Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan CREST, Japan Science and Technology Agency (JST), Saitama 332-0012, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Nakano
authors.affiliation: Department of Development and Differentiation, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Chuma
authors.affiliation: Division of Epigenomics and Development, Medical Institute of Bioregulation, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sasaki
authors.affiliation: Department of Immunology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Kita-ku, Okayama 700-8558, Japan udono@cc.okayama-u.ac.jp.
authors.forename: Heiichiro
authors.initials: H
authors.lastname: Udono
mesh_terms: D000818:Animals; D001120:Arginine / Q000378:metabolism; D060565:Argonaute Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D005333:Fetus / Q000378:metabolism; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics / Q000502:physiology*; D008297:Male; D008745:Methylation; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation; D034741:RNA, Small Interfering / Q000378:metabolism*; D018626:Retroelements; D013737:Testis / Q000196:embryology / Q000378:metabolism
chemical_list: D060565:Argonaute Proteins; D018841:HSP90 Heat-Shock Proteins; C107835:Hspca protein, mouse; C546575:PIWIL4 protein, mouse; D034741:RNA, Small Interfering; D018626:Retroelements; D001120:Arginine