|Budget Amount *help
¥44,590,000 (Direct Cost: ¥34,300,000、Indirect Cost: ¥10,290,000)
Fiscal Year 2013: ¥6,890,000 (Direct Cost: ¥5,300,000、Indirect Cost: ¥1,590,000)
Fiscal Year 2012: ¥6,890,000 (Direct Cost: ¥5,300,000、Indirect Cost: ¥1,590,000)
Fiscal Year 2011: ¥7,670,000 (Direct Cost: ¥5,900,000、Indirect Cost: ¥1,770,000)
Fiscal Year 2010: ¥23,140,000 (Direct Cost: ¥17,800,000、Indirect Cost: ¥5,340,000)
We studied the role of neuregulin (NRG) in the initiation of meiosis, using mutant mice and in vitro cultures. Tamoxifen (TM) injection into Nrg1Ser–/– mutant mice, as well as dominant-negative ErbB4 transgenic mice, decreased proliferation of spermatogonia and meiotic initiation. In cultures of testicular fragments and purified spermatogonia, NRG1 and RA promoted spermatogonial proliferation and meiotic initiation. These results indicate that in juvenile testes RA induces meiosis indirectly through Sertoli cells when NRGs are upregulated and the NRGs directly induce meiosis in spermatogonia through ErbB4 receptor. Collectively, these results indicate that NRGs are essential for the proliferation of spermatogonia and meiotic initiation.
The studies in HeLa cells suggested that p80, which is generated from ErbB4 and translocates to the nuclei, interacts with a-enolase and inhibits NRG1-dependent cell proliferation by impairing the c-myc gene transcription.