active substance regulating differentiation of germ lines

1)RT/PCR法结合Southern杂交结果显示，PMSG给药后1d，小鼠卵巢和颗粒细胞中FasL基因的表达水平最高，而在第5天，FasL基因的表达水平变得非常弱。观察到的FasL mRNA的逐渐下降不能归因于闭锁过程中细胞RNA的普遍降解，PMSG处理的小鼠卵巢和颗粒细胞中存在延伸因子(EF-1a)mRNA的结构性表达就是证明了这一点。此外，用FasL特异的探针进行原位杂交分析证实，FasL特异地定位于大多数卵泡的颗粒细胞中，其表达受PMSG的调节。2)我们发现，在GZ期停滞的未成熟卵母细胞中已经存在MAPK的失活，并且这种失活的激酶仅定位于细胞质中。在GZ/M过渡阶段，部分MAPK在生发泡破裂(GVBD)之前进入生发泡(GV)。此外，免疫印迹分析表明，核MAPK以活性形式存在。为了确定这种活性是否会诱发GVBD，我们将活性MAPK显微注射到未成熟的猪卵母细胞中。注射到细胞质的活性MAPK迅速失活，不能加速GVBD。相反，将MAPK注射到GV明显加速GVBD

1) RT/PCR technique coupled with Southern blot hybridization analysis showed that highest level of FasL mRNA was demonstrated in murine ovaries and granulosa cells 1 day after the administration of PMSG,while the level of FasL mRNA became very weak on the day 5, respectively. The observed gradual decrease in FasL mRNA could not be attributed to a generalized degradation of cellular RNA during atresia, as evidenced by the presence of constitutive expression of elongation factorla (EF-1a) mRNA in murine ovaries and granulosa cells treated with PMSG.Furthermore, in situ hybridization analysis with a FasL-specific probe confirmed that FasL was specifically localized in the granulosa cells of most follicles and its expression was regulated by PMSG administration.2) We found the the inactive MAPK was already present in immature oocytes arrested at the GZ stage and that this inactive kinase was localized exclusively in the cytoplasm. At the GZ/M transition stage, part of the MAPK moved into the germinal vesicle (GV) before germinal vesicle breakdown (GVBD). In addition, immunoblot analysis showed that the nuclear MAPK existed in an active form. To determine whether this active could induce GVBD,we microinjected active MAPK into immature porcine oocytes. The active MAPK injected into the cytoplasm was quickly inactivated and could not accelerate GVBD.In contrast, MAPK injection into the GV markedly accelerated GVBD