| First Author | Ichiyanagi T | Year | 2014 |
| Journal | Nucleic Acids Res | Volume | 42 |
| Issue | 19 | Pages | 11903-11 |
| PubMed ID | 25262350 | Mgi Jnum | J:356915 |
| Mgi Id | MGI:6213456 | Doi | 10.1093/nar/gku881 |
| Citation | Ichiyanagi T, et al. (2014) HSP90alpha plays an important role in piRNA biogenesis and retrotransposon repression in mouse. Nucleic Acids Res 42(19):11903-11 |
| abstractText | HSP90, found in all kingdoms of life, is a major chaperone protein regulating many client proteins. We demonstrated that HSP90alpha, 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 Hsp90alpha 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 Hsp90alpha mutation reduced piRNAs of 24-32 nucleotides, suggesting the presence of both FKBP6-dependent and -independent actions of HSP90alpha. Although DNA methylation and mRNA levels of L1 retrotransposon were largely unchanged in the Hsp90alpha mutant testes, the L1-encoded protein was increased, suggesting the presence of post-transcriptional regulation. This study revealed the specialized function of the HSP90alpha isofom in the piRNA biogenesis and repression of retrotransposons during the development of male germ cells in mammals. |
