The human lipodystrophy gene product, seipin plays physiological roles beyond the adipose tissue

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 524-553-Male Reproductive Endocrinology
Bench to Bedside
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-548
Chihiro Ebihara*1, Ken Ebihara2, Megumi Aizawa Abe2, Tshutomu Tomita1, Toru Kusakabe1, Yuji Yamamoto1, Daisuke Aotani1, Sachiko Yamamoto Kataoka1, Takeru Sakai1, Valentino Milton Gumbilai1, Mingming Zhao1, Kiminori Hosoda2 and Kazuwa Nakao1
1Kyoto University Graduate School of Medicine, Kyoto, Japan, 2Kyoto University Hospital, Kyoto, Japan
Mutations in the Berardinelli-Seip congenital lipodystrophy 2 gene (BSCL2) are the underlying defect in patients with congenital generalized lipodystrophy type 2. BSCL2 encodes a protein called seipin, a 398–amino-acid protein of largely unknown function. It is reported that BSCL2 highly expresses in brain and testis in human. We checked BSCL2 expression in rats and mice and found that it was also high in brain and testis from rats but not in brain from mice. Thus, to investigate the physiological role of seipin, using the method with ENU (N-ethyl-N-nitrosourea) mutagenesis, we generated a seipin deficient (seipin KO) rat that had a premature stop codon (L20X) in BSCL2. In addition to the lipoatrophic phenotype similar to human patients with BSCL2 mutation, seipin KO rats showed impaired spatial working memory and azoospermia. Brain weight and neuron number were decreased in seipin KO rats, suggesting the role of seipin in neural development. Spermatogenesis was markedly impaired in seipin KO rats and seipin gene expression was detected only in mature sperms, suggesting the role of seipin in late phase of spermatogenesis. The present study clearly revealed the physiological roles of seipin not only in adipose tissue but also brain and testis.

Nothing to Disclose: CE, KE, MAA, TT, TK, YY, DA, SYK, TS, VMG, MZ, KH, KN

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm