Analysis on the interactions between germ cells and somatic cells in the developing fish gonads.

1. 为了分析性腺性别分化过程中生殖细胞和体细胞之间的相互作用，分化标志物是必不可少的。从生殖细胞的增殖动力学和超微结构两方面对水稻生殖细胞的性别分化进行了鉴定。本研究对13种凝集素染色的睾丸和卵巢进行组织学观察，发现BPA和SBA染色的精原细胞和卵原细胞的染色性差异，以及BPA、MPA和PNA染色的支持细胞和颗粒细胞的染色性差异。我们还用凝集素对发育中的性腺进行染色。鱼苗中刚孵化的前原细胞和支持细胞不与BPA结合，但在7-8mm鱼苗中睾丸结构的雏形开始构建时，它们被BPA染色。sba阳性生殖细胞出现在刚孵化的雌性鱼苗中，而在小于5-6mm的雄性鱼苗中没有出现。这些结果表明，凝集素可以作为该鱼精原细胞向精原细胞、体腔上皮细胞向支持细胞分化的标志。我们知道，水稻的性别是由y染色体的存在决定的。在对奥米齐鱼（Oryzias）杂交不育的研究中，我们注意到东朝鲜种群的O. latipes与O. curvinotus之间的XY杂交成为雌性，这表明在东朝鲜种群的O. latipes基因存在的情况下，O. curvinotus Y染色体上的睾丸决定基因不能表达。遗传分析表明，X染色体上的基因不参与雄性决定，但有两个以上的常染色体基因与性别决定过程有关。

1. In order to analyze the interactions between germ cells and somatic cells during the sex differentiation of gonads, differentiation markers are indispensable. The sex differentiations of germ cells in Oryzias latipes has been identified from the kinetics of their proliferation as well as from the ultrastructure. In the present study, histological observation on testes and ovaries which were stained with 13 kinds of lectins revealed that we can discern spermatogonia and oogonia from the differences of the stainability with BPA or SBA, also Sertoli cells and granulosa cells with BPA, MPA and PNA.We also stained the developing gonads with lectins. Prespermatogonia and supporting cells in the fry just after hatching did not bind with BPA, but stained with BPA when the rudiments of testicular architecture begin to be constructed in the 7-8mm fry. SBA-positive germ cells noted in the female fry just after hatching, whereas they did not appeared in males younger than 5-6mm fry. These results indicate that lectins can be a differentiation marker from prespermatogonia to spermatogonia as well as from coelomic epithelial cells to Sertoli cells in this fish.2. It is known that the sex is determined by the presence of Ychromosome in Oryzias latipes. In the study about the hybrid sterility in fishes of Oryzias, we noticed that XY hybrids between O. latipes of east Korean population and O. curvinotus become female, an indication that the testis determining gene (s) on Y chromosome of O. curvinotus cannot be expressed in the presence of genes of O. latipes of east Korean population. The genetic analysis clarified that the genes on X chromosome dose not involved in the male determination, but that more than two autosomal genes have a relation to the sex-determining processes.