title: Heat shock transcription factor 1 is involved in quality-control mechanisms in male germ cells.
abstract: Quality-control mechanisms in spermatogenesis are important to eliminate injured or abnormal cells, thereby protecting the organism from abnormal development in the next generation. The processes of spermatogenesis are highly sensitive to high temperatures; however, the mechanisms by which injured germ cells are eliminated remain unclear. Here, we found that heat shock proteins are not induced in male germ cells in response to thermal stress, although heat shock transcription factor 1 (HSF1) is activated. Using HSF1-null mice, we showed that apoptosis of pachytene spermatocytes was markedly inhibited in testes with a single exposure to heat and in the cryptorchid testes, indicating that HSF1 promotes apoptotic cell death of pachytene spermatocytes exposed to thermal stress. In marked contrast, HSF1 acts as a cell-survival factor of more immature germ cells, probably including spermatogonia, in testes exposed to high temperatures. These results demonstrate that HSF1 has two opposite roles in male germ cells independent of the activation of heat shock genes.
authors.affiliation: Department of Biochemistry and Molecular Biology, Yamaguchi University School of Medicine, Japan.
authors.forename: Hanae
authors.initials: H
authors.lastname: Izu
authors.forename: Sachiye
authors.initials: S
authors.lastname: Inouye
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Fujimoto
authors.forename: Koji
authors.initials: K
authors.lastname: Shiraishi
authors.forename: Katsusuke
authors.initials: K
authors.lastname: Naito
authors.forename: Akira
authors.initials: A
authors.lastname: Nakai
mesh_terms: D000818:Animals; D016923:Cell Death; D002470:Cell Survival; D003456:Cryptorchidism / Q000473:pathology / Q000503:physiopathology; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D015870:Gene Expression; D000076249:Heat Shock Transcription Factors; D018882:Heat Stress Disorders / Q000473:pathology / Q000503:physiopathology; D008297:Male; D051379:Mice; D008817:Mice, Mutant Strains; D013087:Spermatids / Q000166:cytology / Q000502:physiology*; D013091:Spermatogenesis / Q000502:physiology*; D013093:Spermatogonia / Q000166:cytology / Q000502:physiology*; D014157:Transcription Factors
chemical_list: D004268:DNA-Binding Proteins; D000076249:Heat Shock Transcription Factors; D014157:Transcription Factors