Effect of epigenetic aberrations on germ cells and interchromosomal coordination of gene expression in mouse spermatogenesis

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K15173
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: General anatomy (including histology/embryology)
• Research Institution: Nagasaki University
• Principal Investigator: KOJI Takehiko 長崎大学, 医歯薬学総合研究科(医学系), 教授 (30170179)
• Co-Investigator(Kenkyū-buntansha): 柴田 恭明 長崎大学, 医歯薬学総合研究科(医学系), 講師 (80253673) ; 遠藤 大輔 長崎大学, 医歯薬学総合研究科(医学系), 助教 (90516288) ; 末松 貴史 長崎大学, 医歯薬学総合研究科(医学系), 技術職員 (70264249)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: DNAメチル化 / ヒストン修飾 / アポトーシス / PGK1 / PGK2 / in situ PCR / 精子形成過程 / マウス精巣

Outline of Final Research Achievements

In the present study, we found a gradual increase of CCGG methylation till step 11-12 spermatids in normal mouse spermatogenesis unlike the case of 5-methylcytosine (5MC). To mimic the level of DNA methylation, we injected 5-azadC into mice and found that hypomethylation leads to induce spermatogonial apoptosis. Since acetylation pattern of histone H3 was known to change depending upon differentiation stage of germ cells, we examined the effect of HDAC inhibitors such as valproic acid and SAHA on spermatogenesis. Unlike Na phenylbutylate, spermatogonial apoptosis was induced, indicating the different mechanisms among drugs. When Dnmt1 was knock-downed by shRNA vector transfection, the expression of 5MC was markedly decreased, accompanying abnormalities in chromosomal distribution in pachytene spermatocytes. However, the analysis of the distance between PGK1 and PGK2 genes by in situ PCR was not successful in tissue sections, indicating a better use of isolated germ cells.

Free Research Field

分子解剖学