You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research (I)1 Apr 2013819 ANDROGEN RECEPTOR IS NEGATIVELY REGULATED BY FEMINIZATION FACTOR 1B (FEM1B) IN MAMMALIAN TESTIS Shoichiro Iwatsuki, Shoichi Sasaki, Yasue Kubota, Hiroki Kubota, Yukihiro Umemoto, Yutaro Hayashi, and Kenjiro Kohri Shoichiro IwatsukiShoichiro Iwatsuki Nagoya, Japan More articles by this author , Shoichi SasakiShoichi Sasaki Nagoya, Japan More articles by this author , Yasue KubotaYasue Kubota Nagoya, Japan More articles by this author , Hiroki KubotaHiroki Kubota Nagoya, Japan More articles by this author , Yukihiro UmemotoYukihiro Umemoto Nagoya, Japan More articles by this author , Yutaro HayashiYutaro Hayashi Nagoya, Japan More articles by this author , and Kenjiro KohriKenjiro Kohri Nagoya, Japan More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.385AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Mammalian Fem1b (Feminization Factor 1b) is a homolog of nematode fem-1, which is a sex-determining factor of gametocytes. Although it is suggested that mammalian Fem1b plays roles in maintenance of testicular function, its mechanism remains to be solved. In this study, we evaluated expression patterns of Fem1b in rat testis and its contribution to androgen regulation in Leydig and Sertoli cell. METHODS Gene expression of Fem1b in normal Sprague-Dawley rat testes according to the age in weeks (4 to 12 weeks) was assessed by real-time polymerase chain reaction (RT-PCR) and the loci of expressions were assessed by immunohistochemistry. To assess androgen regulation in Leydig and Sertoli cells, we knocked down Fem1b gene expression by siRNA against Fem1b using I-10 cell (Leydig cell line) and TM4 cell (Sertoli cell line). After 48 hours from administration of siRNA, sex steroidogenesis enzymes (Cyp11a1 and Hsd3β mRNA levels in the I-10 cells and androgen receptor mRNA level in the TM4 cells were evaluated. RESULTS Fem1b mRNA expression remarkably increased up to 2.5-fold at 4 to 6 weeks of age, when spermatogenesis began. By immunohistochemistry, Fem1b was detected in the cytoplasm of spermatocytes, round spermatids and elongate spermatids. It was also detected in interstitial cells, especially in Leydig cells. Cyp11a1 and Hsd3β mRNA levels in the I-10 cells were not affected by gene knocking down of Fem1b. However, androgen receptor mRNA levels in the TM4 cells increased by Fem1b knockdown. CONCLUSIONS Fem1b mRNA expression remarkably increased up to 2.5-fold at 4 to 6 weeks of age, when spermatogenesis began. By immunohistochemistry, Fem1b was detected in the cytoplasm of spermatocytes, round spermatids and elongate spermatids. It was also detected in interstitial cells, especially in Leydig cells. Cyp11a1 and Hsd3âÒ mRNA levels in the I-10 cells were not affected by gene knocking down of Fem1b. However, androgen receptor mRNA levels in the TM4 cells increased by Fem1b knockdown. CONCLUSIONS In this study, we showed that Fem1b expression is localized in spermatocytes, spermatids and Leydig cells in rat testis. We also showed that knocking down Fem1b expression resulted in an increase of androgen receptor expression, suggesting that Fem1b does not contribute to steroidogenesis, which is stimulated by the hypothalamus-pituitary-testis axis, but contributes to the regulation of androgen receptor expression. It is suggested that Fem1b may be a negative-regulatory factor of androgen sensitivity in the mammalian testis. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e336 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Shoichiro Iwatsuki Nagoya, Japan More articles by this author Shoichi Sasaki Nagoya, Japan More articles by this author Yasue Kubota Nagoya, Japan More articles by this author Hiroki Kubota Nagoya, Japan More articles by this author Yukihiro Umemoto Nagoya, Japan More articles by this author Yutaro Hayashi Nagoya, Japan More articles by this author Kenjiro Kohri Nagoya, Japan More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...