active substance regulating differentiation of germ lines

1)RT/PCR和Southern杂交结果显示，PMSG处理后1d，小鼠卵巢和颗粒细胞中FasL mRNA表达水平最高，第5天，FasL mRNA表达水平下降。观察到的FasL mRNA的逐渐减少不能归因于闭锁期间细胞RNA的普遍降解，如在用PMSG处理的小鼠卵巢和颗粒细胞中存在延伸因子Ia（EF-1a）mRNA的组成型表达所证明的。原位杂交分析与FasL-特异性探针证实FasL特异性定位于大多数卵泡的颗粒细胞，其表达受PMSG的调控。我们发现在GZ期停滞的未成熟卵母细胞中已经存在失活的MAPK，并且这种失活的激酶仅定位于细胞质中。在GZ/M转换期，部分MAPK在芽囊泡破裂（GVBD）前进入芽囊泡（GV）。免疫印迹分析表明，细胞核MAPK以活性形式存在。为了确定这种活性是否可以诱导GVBD，我们将活性MAPK显微注射到未成熟的猪卵母细胞中。将活化的MAPK注入细胞质后迅速失活，不能促进GVBD，而将MAPK注入GV则明显促进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