title: Mice stage-specific claudin 3 expression regulates progression of meiosis in early stage spermatocytes.
abstract: Claudin 3 is a protein component of the tight junction strands. Tight junctions between adjacent Sertoli cells form the blood-testis barrier (BTB). During spermatogenesis, seminiferous stage-specific expression of claudin 3 is believed to regulate the migration of preleptotene/leptotene spermatocytes across the BTB. Here, we determined the cell types expressing claudin 3 in adult mouse testis and investigated spermatogenesis after testis-specific in vivo knockdown of claudin 3. The results of in situ hybridization revealed that claudin 3 mRNA was predominantly expressed in germ cells near the basal lamina of seminiferous tubules at stages VI-IX. Furthermore, claudin 3 protein was localized not only to the BTB but also to the cell membrane of STRA8-expressing preleptotene/leptotene spermatocytes in the testis of adult ICR.Cg-Tg(Stra8-EGFP)1Ysa/YsaRbrc mice. Although claudin 3 knockdown did not affect BTB integrity, it did cause a partial delay in spermatocyte migration across the BTB. Moreover, claudin 3 knockdown resulted in a prolonged preleptotene phase during spermatogenesis. These data indicate that the seminiferous stage-specific expression and localization of claudin 3 during spermatogenesis regulate the progression of meiosis by promoting germ cell migration across the BTB.
authors.affiliation: Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Chihara
authors.forename: Ryoyo
authors.initials: R
authors.lastname: Ikebuchi
authors.forename: Saori
authors.initials: S
authors.lastname: Otsuka
authors.forename: Osamu
authors.initials: O
authors.lastname: Ichii
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Hashimoto
authors.forename: Atsushi
authors.initials: A
authors.lastname: Suzuki
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Saga
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kon
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism; D000818:Animals; D001814:Blood-Testis Barrier; D002465:Cell Movement / Q000502:physiology; D062465:Claudin-3 / Q000096:biosynthesis / Q000235:genetics*; D005260:Female; D055785:Gene Knockdown Techniques; D008297:Male; D008540:Meiosis; D051379:Mice; D008810:Mice, Inbred C57BL; D012708:Sertoli Cells / Q000378:metabolism*; D013090:Spermatocytes / Q000378:metabolism*; D013091:Spermatogenesis
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D062465:Claudin-3; C568123:Cldn3 protein, mouse; C102019:Stra8 protein, mouse
keywords: blood-testis barrier; claudin 3; meiosis; spermatogenesis; tight junction