IMMUNOGENETICS OF SPERMATOZOA, EGGS, AND EMBRYOS

小鼠17号染色体上的T/t复合体包含许多突变基因 在早期胚胎发育过程中发挥作用，以及其他影响 精子的分化。因此，它一直在密集地 作为分析差异化及其应用的模型系统而被研究 基因控制。然而，直到最近，T/T复合体还不是 在分子生物学方面是可接近的，因为遗传学和分子 在DNA结构水平上进行研究所需的标记没有 可用。来自这个实验室的新结果，是通过结合 遗传学、血清学和分子技术现在已经提供了 进行密集分子分析所必需的材料。我们已经定义了7 T致死基因作为非等位基因但功能相关，并具有准确的 关于它们彼此之间和彼此之间的位置的信息 染色体标记，包括MHC的TL、K、I和BD区。 其中四个致命基因夹杂着MHC基因。我们有 产生了一组广泛的重组染色体，由 在两个不同的t-单倍型之间杂交，并定义了它们的 断点。其中14个是H-2内重组体， 7种MHC的限制性片段多态定义的断点 探测器。因此，对于分子来说，这是第一次有机会 对哺乳动物体内调节发育的基因复合体的研究。 这个项目提出了三个相辅相成的战略来定义 突变T/t复合体的分子组织及其与野生型的比较 键入对应基因，并鉴定和克隆该区域的突变基因。 (1)染色体行走在纯合子t-w5 DNA的粘粒基因组文库中， 以H-2 I类基因的探针和K区探针为起始 距离t-w5致死突变非常近(0-0.1 cM)的MAP，将产生 可以与wold类型进行比较的MHC的限制图。(2)A类 类似的染色体行走在t-12/t-w5DNA的粘粒基因组文库中 允许比较t-12和t-w5的MHC限制图。 这种比较将特别有趣，因为它将给出 关于DNA结构进化变化的信息，这些变化可能发生在 实际上没有重组。它还可能有助于准确地确定结构 与t-12和t-w5致死突变相关的异常。(3) 人精子发生过程中17号染色体表达序列的克隆 识别和定位T/T相关基因的正常和突变睾丸 复杂的表型。

The T/t complex on mouse chromosome 17 contains a number of mutant genes that function during early embryonic development, and others that affect the differentiation of spermatozoa. Thus it has been intensively investigated as a model system for analyzing differentiation and its genetic control. Until recently, however, the T/t complex was not approachable in terms of molecular biology since the genetic and molecular markers necessary for investigation at the level of DNA structure were not available. New results from this laboratory, obtained with a combination of genetic, serological, and molecular techniques have now provided the necessary material for intensive molecular analysis. We have defined 7 t-lethal genes as non-allelic but functionally related, and have accurate information on their location relative to one another and to other chromosome markers, including the TL, K, I, anbd D regions of the MHC. Four of the lethal genes are interspersed with MHC genes. We have generated an extensive panel of recombinant chromosomes, derived by crossing over between two different t-haplotypes, and defined their breakpoints. Fourteen of these are intra H-2 recombinants, with breakpoints defined by restriction fragment polymorphisms for 7 MHC probes. Thus for the first time the opportunity exists for the molecular investigation of a gene complex that regulates development in a mammal. This project proposes three complementary strageties to define the molecular organization of the mutant T/t complex and compare it to its wild type counterpart, and to identify and clone mutant genes in that region. (1) Chromosomal walking in a cosmid genomic library of homozygous t-w5 DNA, initiated with probes to H-2 class I genes and with K region probes that map very close (0-0.1 cM) to the t-w5 lethal mutation, will produce a restriction map of the MHC that can be compared to wold type. (2) A similar chromosomal walk in a cosmid genomic library of t-12/t-w5 DNA will permit a comparison of the restriction maps of the MHC of t-12 with t-w5. This comparison will be especially interesting because it will give information on evolutionary changes in DNA structure that can occur in the virtual absence of recombination. It also may help to pinpoint structural aberrations associated with the t-12 and t-w5 lethal mutations. (3) Cloning of chromosome 17 sequences expressed during spermatogenesis in normal and mutant testes to identify and map genes responsible for T/t complex phenotypes.