PLATFORM SESSION 11. GAMETE BIOLOGY AND GAMETOGENESIS II
Monday, August 2, 2004
2:00 PM–4:00 PM
Chair: John McCarrey
Co-Chair: Barbara Sotolongo
(306) IDENTIFICATION OF A NOVEL MALE GERM CELL-SPECIFIC GENE TESF-1.
Fan, Jun 1, Akabane, Hiroto1, Richardson, Laura 2, Zhu, Guo-Zhang1, 1 Marshall University, Huntington, WV2 Marshall University, School of Medicine, Huntington, WV
ABSTRACT- Mammalian spermatogenesis is a precisely regulated developmental process in which germ cell self-renewal, apoptosis, proliferation, and differentiation are carefully controlled. Recent studies pointed out that this control relies on a number of unique regulatory mechanisms executed by many germ cell-specific factors. The objective of this study was to identify such a germ cell-specific factor to further understand the course of spermatogenesis. Initially, we cloned a 1.4 kb gene fragment with the 3′ poly A end from the BALB/C mouse testis cDNA pool. Further Northern blot analysis displayed that the expression of this gene was exclusively in testis, and the transcribed mRNA was about 2.0 kb. Accordingly, we tentatively named this gene as Testis Specific Factor-1 (TESF-1). The RT-PCR result, using the total RNA samples from the testes harvested at different postnatal days, showed that TESF-1 had a highly specific developmental pattern of expression in testis, with the starting expression time point around the 20th postnatal day, suggesting that TESF-1 is a male germ cell-specific gene. Indeed, the restricted expression of TESF-1 in male germ cells was confirmed by the observation that we were not able to amplify the TESF-1 gene product from at/at homozygous mutant testes, which lack germ cells. The full length cDNA of TESF-1, obtained through the 5′ Rapid Amplification of cDNA Ends (RACE) experiment, contains an open reading frame of 1056 bp. The deduced amino acid sequence contains a leucine zipper motif, a potential nuclear targeting sequence, two potential cAMP- and cGMP-dependent protein kinase phosphorylation sites, and a basic isoelectric point (=9.948). These results indicate that TESF-1 is a novel male germ cell-specific gene, and its protein product may function as a nuclear factor involved in the regulation of spermatogenesis.
KEY WORDS: male germ cell-specific, spermatogenesis, novel gene