Department of Biology, University of Fribourg, Fribourg, Switzerland.
Adv Exp Med Biol. 2013;757:41-69. doi: 10.1007/978-1-4614-4015-4_3.
How is sex determined? In the animal kingdom, there are diverse sets of mechanisms for determining organismal sex, with the predominant ones being chromosomally based, either a dominant-acting sex chromosome or the ratio of the number of X chromosome to autosomes, which lead to oocyte-producing females and sperm-producing males. The resulting germline sexual phenotype is often the logical consequence of somatic sex determination. In this respect however, the Caenorhabditis elegans hermaphrodite is different from mammals and Drosophila. In fact in the C. elegans hermaphrodite germline, male gametes are transiently produced in a female body during larval development. To override chromosomal signals, sex determination of germ cells strongly depends on post-transcriptional regulation. A pivotal role for male gamete production (spermatogenesis) is played by the fem-3 mRNA, which is controlled through FBF and other RNA-binding proteins or splicing factors. Thanks to its powerful genetics, transparent body, small size, and the ability to make sperm and oocytes within one individual, C. elegans represents an excellent system to investigate cellular differentiation and post-transcriptional control.
性别是如何决定的？在动物界，存在多种决定生物体性别的机制，其中主要的机制是基于染色体的，要么是显性作用的性染色体，要么是 X 染色体与常染色体数量的比例，这导致产生卵子的雌性和产生精子的雄性。由此产生的生殖细胞性表型通常是体性决定的逻辑结果。然而，在这方面，秀丽隐杆线虫雌雄同体与哺乳动物和果蝇不同。事实上，在秀丽隐杆线虫雌雄同体的生殖细胞中，雄性配子在幼虫发育过程中短暂地在雌性体内产生。为了克服染色体信号，生殖细胞的性别决定强烈依赖于转录后调控。雄性配子产生（精子发生）的关键作用是由 fem-3 mRNA 发挥的，它通过 FBF 和其他 RNA 结合蛋白或剪接因子进行控制。由于其强大的遗传学、透明的身体、小巧的体型，以及在一个个体中产生精子和卵子的能力，秀丽隐杆线虫是研究细胞分化和转录后调控的极佳系统。
