Fujita Masaki, Takasaki Teruaki, Nakajima Noboru, Kawano Taizo, Shimura Yoshiro, Sakamoto Hiroshi
Department of Life Science, Graduate School of Science and Technology, Kobe University, 1-1 Rokkodaicho, Nadaku, Kobe 657-8501, Japan.
Mech Dev. 2002 Jun;114(1-2):61-9. doi: 10.1016/s0925-4773(02)00058-8.
We identified MRG-1, a Caenorhabditis elegans chromodomain-containing protein that is similar to the human mortality factor-related gene 15 product (MRG15). RNA-mediated interference (RNAi) of mrg-1 resulted in complete absence of the germline in both hermaphrodite and male adults. Examination of the expression of PGL-1, a component of P granules, revealed that two primordial germ cells (PGCs) are produced during embryogenesis in mrg-1(RNAi) animals, but these PGCs cannot undergo mitotic proliferation, and they ultimately degenerate during post-embryonic development. Zygotic RNAi experiments using RNAi-deficient hermaphrodites and wild-type males demonstrated that MRG-1 functions maternally. Moreover, immunoblot analysis using mutant animals with germline deficiencies indicated that MRG-1 is synthesized predominantly in oocytes. These results suggest that MRG-1 is required maternally to form normal PGCs with the potential to start mitotic proliferation during post-embryonic development.
我们鉴定出了MRG-1，一种秀丽隐杆线虫中含染色质结构域的蛋白质，它与人类死亡因子相关基因15产物（MRG15）相似。对mrg-1进行RNA介导的干扰（RNAi）导致雌雄同体和雄性成虫的生殖系完全缺失。对P颗粒成分PGL-1的表达进行检测发现，在mrg-1（RNAi）动物的胚胎发育过程中会产生两个原始生殖细胞（PGC），但这些PGC不能进行有丝分裂增殖，它们最终在胚胎后期发育过程中退化。使用RNAi缺陷型雌雄同体和野生型雄性进行的合子RNAi实验表明，MRG-1在母体中发挥作用。此外，使用生殖系缺陷的突变动物进行的免疫印迹分析表明，MRG-1主要在卵母细胞中合成。这些结果表明，MRG-1在母体中是形成具有在胚胎后期发育过程中开始有丝分裂增殖潜力的正常PGC所必需的。
