Cloning and Characterization of Genes Specifically Expressed in Haploid Germ Cells

精子发生是一个复杂的分化过程，涉及到许多重要的生物学现象，如精原细胞的增殖和分化、减数分裂和单倍体生殖细胞的产生以及精子形成过程中的形态发生。睾丸特异表达基因的分离以及生殖细胞分化不同阶段特异表达基因的分离为研究精子发生提供了新的思路，而消减克隆技术是分离生殖细胞特异表达基因的有效方法。17日龄小鼠睾丸未发生单倍体生殖细胞分化。如果我们能够从成年睾丸中减去这种17日龄睾丸的cDNA文库，则可以分离出仅来源于单倍体生殖细胞的cONA克隆。由于这种消减cDNA文库制备技术的改进，已分离到许多在单倍体生殖细胞中特异表达的cDNA克隆，通过对这些基因功能的研究，必将在精子发生的研究乃至控制生殖细胞分化复杂过程的临床应用方面取得重大进展。

Spermatogenesis is a complex differentiation process involving many interesting phenomena that are biologically important, such as spermatogonial proliferation and differentiation, meiosis and generation of haploid germ cells and morphogenesis on the way to the sperm. Isolation of genes specifically expressed in testes and also specifically expressed in different steps of germ cell differentiation sheds new light on understanding the spermatogenesis.Subtraction cloning would be effective to isolate novel genes that were germ-cell-specific. No haploid germ cell differentiation occurs to the testes of 17 days old mouse testis. If we can subtract a cDNA library of such 17 days old testes from adult testits, cONA clones derived solely from the haploid germ cells could be isolated. Because of technical improvement for preparing this type of subtraction cDNA library, many cDNA clones specifically expressed in haploid germ cells have been isolated.By the characterization of the function of these genes we will surely make great progress on the study of spermatogenesis and even on new clinical applications that will control the complicated processes of the germ cell differentiation.