Kobayashi S, Amikura R, Okada M
Institute of Biological Sciences, University of Tsukuba, Ibaraki, Japan.
Int J Dev Biol. 1994 Jun;38(2):193-9.
This article reviews recent studies on cytoplasmic factors for germ-line establishment in Drosophila and Xenopus. In a variety of animal groups, the cytoplasmic factors for germ-line differentiation have been postulated to be localized in the germ plasm. We have found that mitochondrial large rRNA (mtlrRNA) is present in germinal granules, the distinctive morphological markers of germ plasm in the fruit-fly and the frog. MtlrRNA has been identified as a cytoplasmic factor that induce pole cells, the progenitor of the germ line, in uv-sterilized Drosophila embryos. The developmental stages of Xenopus at which mtlrRNA is present in germinal granules correspond to the stages of germ line segregation. Based on our findings and available data on posterior class gene products as well as on classical developmental biology of germ cells, we discuss the probable role of mtlrRNA in germ-line segregation from the somatic line in these animals.
本文综述了近期关于果蝇和非洲爪蟾生殖系建立的细胞质因子的研究。在各种动物群体中，生殖系分化的细胞质因子被认为定位于生殖质中。我们发现线粒体大核糖体RNA（mtlrRNA）存在于生殖颗粒中，生殖颗粒是果蝇和青蛙生殖质独特的形态学标志。MtlrRNA已被鉴定为一种细胞质因子，可在紫外线灭菌的果蝇胚胎中诱导生殖系祖细胞极细胞的产生。非洲爪蟾生殖颗粒中存在mtlrRNA的发育阶段与生殖系分离阶段相对应。基于我们的研究结果以及关于后类基因产物的现有数据，以及生殖细胞的经典发育生物学，我们讨论了mtlrRNA在这些动物中生殖系与体细胞系分离过程中可能发挥的作用。
