ANALYSIS OF PROGRAMMED CELL DEATH IN FILAMENTOUS FUNGI

这项拨款提案的目的是遗传和分子表征在丝状真菌，神经孢子草营养不相容。植物性不相容性是一种程序性细胞死亡，可以防止传染因子如分枝病毒在整个真菌种群中的转移。营养不相容在丝状真菌中是普遍存在的，但在s.s cerevisiae和s.p ombe中显然不存在，可能是因为它们的单细胞或假菌丝生长习惯。与其他丝状真菌不同，N. crassa具有遗传上明确的营养不相容系统（het基因座），并且遗传和分子工具都是可用的。我们之前已经克隆并鉴定了三个het位点，交配型，het-c和het-6。本申请描述了阐明高温-碳介导的氮草营养不相容机制的实验。我们关于het-c介导的营养不相容基础的假设是，在一个共同的细胞质中，可选择的het-c多肽的共定位通过干扰有丝分裂的调节触发死亡。我们相信，对N. crassa营养不亲和性的分析将揭示细胞周期调节与诱导简单真核生物程序性细胞死亡之间的联系。本奖助金提案的具体目标是：1。为了描述对het-c等位基因特异性的要求，2。2 .在细胞生长和程序性细胞死亡期间，将HET-C定位在细胞内。利用生化和遗传分析分析植物不亲和的机制。植物不亲和性的生化和遗传分析。对丝状真菌营养不相容的分析将为程序性细胞死亡的进化提供信息，并可能揭示其他方法无法获得的细胞周期调节和细胞死亡的机制。了解丝状真菌的细胞程序性死亡途径可能为开发抗丝状真菌引起的人类疾病的真菌特异性药物提供独特的靶点。

The aim of this grant proposal is to genetically and molecularly characterize vegetative incompatibility in the filamentous fungus, Neurospora crass. Vegetative incompatibility is a type of programmed cell death that can prevent transfer of infectious agents such as mycoviruses, throughout a fungal population. Vegetative incompatibility is universal in filamentous fungi, but is apparently absent from S. cerevisiae and S. pombe, presumably because of their unicellular or pseudohyphal growth habit. Unlike other filamentous fungi, N. crassa has a genetically well-defined vegetative incompatibility system (het loci) and both genetic and molecular tools are available. We have previously cloned and characterized three het loci, mating-type, het-c and het-6. This grant proposal describes experiments to elucidate the mechanism of vegetative incompatibility mediated by het-c in N. crassa. Our hypothesis concerning the basis of het-c mediated vegetative incompatibility states that the co-localization of alternative het-c polypeptides in a common cytoplasm triggers death by interference with the regulation of mitosis. We believe that an analysis of vegetative incompatibility in N. crassa will reveal links between cell cycle regulation and induction into programmed cell death in a simple eukaryote. The Specific Aims of this grant proposal are 1. To delineate the requirements for het-c allelic specificity, 2. Localize HET-C within the cell during growth and during programmed cell death, 3. To dissect the mechanism of vegetative incompatibility using both biochemical and genetic analyses. The analysis of vegetative incompatibility using both biochemical and genetic analyses. The analysis of vegetative incompatibility in filamentous fungi will provide information on the evolution of programmed cell death and may uncover mechanisms of cell cycle regulation and cell death that are not accessible by other means. Understanding the pathway of programmed cell death in filamentous fungi may provide unique targets for the development of fungal-specific drugs to combat human diseases caused by filamentous fungi.