MECHANISM OF NUCLEAR FUSION IN YEAST

酵母梭菌斑和相关的微管介导了 核在交配过程中。 通过识别基因和基因产物 我们的目标是确定核聚变的组成部分， 梭形菌斑及其作用机制。 纺锤体斑块是 广泛的兴趣，因为它是唯一的组织者微管在酵母 cell. 对任何微管的功能机制知之甚少 主办方 因此，了解核聚变的机制是 可能对理解一系列广泛的现象很重要 所有真核细胞共有的功能，例如细胞器运动、膜和 细胞器融合，以及微管的调节和功能， 有丝分裂和减数分裂。 酵母是一种很容易被操纵的有机体 基因，这应该允许快速分析这些非常复杂的 流程. 我们将讨论以下具体的实验目标： 1)一个核融合基因KARI的功能的全谱， 有丝分裂，核融合和孢子形成，将由 结合基因突变的遗传分析和 基因产物的亚细胞定位。 基因与 KARI基因将通过抑制不同KARI的突变来识别 突变。 2)核聚变的机制将通过发展 一个体外核聚变系统 这些蛋白质是 核融合将在体外核融合测定中表征。 3)核聚变的途径将通过分离 核融合所需的其他基因突变。 的 不同基因的功能将按照相互转换的顺序排列 不同突变体的实验和细胞学。 核融合基因 将通过体外诱变和基因置换分离和分析 以确定它们在纺锤体斑块的有丝分裂功能中的作用。

The yeast spindle plaque and associated microtubules mediate the fusion of nuclei during mating. By identifying the genes and gene products responsible for nuclear fusion we aim to identify the components of the spindle plaque and the mechanism of its function. The spindle plaque is of wide interest as it is the sole organizer of microtubules in the yeast cell. Little is known about the mechanism of function of any microtubule organizer. Therefore understanding of the mechanism of nuclear fusion is likely to be important to the understanding of a broad set of phenomena common to all eukaryotic cells such as organelle movement, membrane and organelle fusion, and the regulation and function of microtubules in mitosis and meiosis. Yeast is an organism which is easily manipulated genetically, which should allow rapid analysis of these very complex processes. We will address the following specific experimental aims: 1) The full spectrum of functions on one nuclear fusion gene, KARI, in mitosis, nuclear fusion and sporulation, will be determined by a combination of the genetic analysis of mutations in the gene and the subcellular localization of the gene product. Genes that interact with the KARI gene will be identified by mutations that suppress different KARI mutations. 2) The mechanism of nuclear fusion will be examined by the development of an in vitro system for nuclear fusion. The proteins that are required for nuclear fusion will be characterized in the in vitro nuclear fusion assay. 3) The pathway of nuclear fusion will be dissected by the isolation of mutations in the other genes that are required for nuclear fusion. The functions of the different genes will be ordered by reciprocal shift experiments and cytology of the different mutants. Nuclear fusion genes will be isolated and analyzed by in vitro mutagenesis and gene replacement to determine their role in the mitotic functions of the spindle plaque.