IMMUNOGENETICS OF SPERMATOZOA, EGGS, AND EMBRYOS

小鼠17号染色体上的T/t复合体含有多个突变基因 在早期胚胎发育过程中发挥作用， 精子的分化。 因此， 作为分析分化及其 基因控制 然而，直到最近，T/t复合体还没有被发现。 在分子生物学方面是平易近人的，因为遗传和分子 在DNA结构水平上进行研究所需的标记物没有 available. 这个实验室的新结果， 遗传学、血清学和分子技术的发展， 进行深入分子分析的必要材料。 我们定义了7 t-致死基因为非等位基因，但功能相关，并具有准确的 关于它们相对于彼此以及相对于其他 染色体标记，包括MHC的TL、K、I和D区。 其中四个致命基因散布着MHC基因。 我们有 产生了大量的重组染色体， 两个不同的t-单倍型之间的交叉，并定义了它们的 断点。 其中14个是内部H-2重组体， 由7种MHC的限制性片段多态性定义的断点 probes. 因此，第一次有机会存在的分子 研究一种调节哺乳动物发育的基因复合体。 该项目提出了三个互补的战略来定义 突变T/t复合物的分子组织，并将其与其野生型进行比较 型对应物，并鉴定和克隆该区域的突变基因。 (1)纯合t-w5 DNA粘粒基因组文库中的染色体步移， 用H-2 I类基因探针和K区探针启动， 图非常接近（0-0.1厘米）的t-w5致死突变，将产生一个 可以与野生型比较的MHC限制性图谱。 (2)一 在t-12/t-w5 DNA粘粒基因组文库中类似的染色体步移将 允许比较t-12与t-w5的MHC的限制性图谱。 这种比较将特别有趣，因为它将给出 DNA结构进化变化的信息，可以发生在 几乎没有重组。 它也可能有助于确定 与T-12和T-W5致死突变相关的畸变。 （三） 17号染色体精子发生过程中表达序列的克隆 正常和突变的睾丸，以确定和映射基因负责T/t 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.