Genetics of Neurospora

脉孢菌遗传学

• 批准号: 0235698
• 负责人: David Perkins
• 金额: $ 12.74万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-15 至 2005-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0235698&HistoricalAwards=false
• 关键词: Genetics; Neurospora

Ongoing projects take advantage of this laboratory's long experience with Neurospora biology and genetics. The projects concern mutational and epigenetic gene silencing, developmental events in the ascus, meiotic drive, and the delineation of species. Most of the experiments center on the sexual phase of the life cycle and exploit features of Neurospora that make it advantageous for investigations that cannot be readily carried out with yeast. Examples include the following: (1) Genetics and programming of ascus development. The expression and sites of action of genes known to affect the sexual phase will be examined using green fluorescent protein (GFP). Microscopic studies will continue on the effect of unpaired DNA in silencing genes that are expressed in the sexual phase.. (2) The reproductive genetics and biology of N. tetrasperma. Ascus development in this species is reprogrammed to produce self-fertile heterokaryotic products. Crossing over is abolished between the mating type locus and the centromere and recombination is also blocked over most of the mating-type chromosome. The genetic basis of the block is being studied, and modes of ascus programming are being examined in 4-spored species of other genera. (3) Cryptic drive elements in N. tetrasperma. In 8-spored asci, ascospores with sensitive nuclei are killed in crosses that are heterozygous for a Spore-killer meiotic drive element (Sk). Sensitive nuclei survive, however, if they are enclosed in the same ascospore with a killer nucleus. Because N. tetrasperma normally has two types of nuclei in each heterokaryotic ascospore, Sk elements may be present even though they are not apparent. Experiments with strains from natural populations will examine this possibility. (4) A locus-specific mutator. Crosses involving a particular allele of the eas gene in N. crassa produce progeny that are mutated at a specific unlinked locus. The behavior suggests that a duplicate copy of the target gene is linked to the eas mutation, resulting in RIP (repeat induced point mutation). This hypothesis is being tested using crosses homozygous for a mutant that is deficient in RIP.This laboratory has long been devoted to developing Neurospora as a model organism. Model organisms are great assets to science, for the insights gained from them can be used to guide and often accelerate studies of other related but less well-understood organisms. The vast store of genetic and biological information to which the laboratory has contributed makes Neurospora an ideal reference organism with which to compare other filamentous fungi, including plant and animal pathogens, commercially important species, and innumerable ecologically important forms.

正在进行的项目利用了该实验室在脉孢菌生物学和遗传学方面的长期经验。这些项目涉及突变和表观遗传基因沉默，发育中的事件，减数分裂驱动，物种的划分。大多数实验集中在生命周期的有性阶段，并利用脉孢菌的特征，使其有利于研究，不能容易地进行酵母。例如：（1）遗传学和编程的可持续发展。将使用绿色荧光蛋白（GFP）检查已知影响有性阶段的基因的表达和作用位点。显微镜研究将继续研究未配对DNA在沉默性阶段表达的基因中的作用。(2)本文对N.四精子。该物种的子囊发育被重新编程以产生自能生殖的异源产物。交配型基因座和着丝粒之间的交换被取消，重组也被阻止在大多数交配型染色体上。正在研究该区块的遗传基础，并正在研究其他属的4孢子物种的基因编程模式。(3)N中的隐藏驱动元件。四精子。在8孢子子囊中，具有敏感核的子囊孢子在杂交中被杀死，所述杂交对于孢子杀伤减数分裂驱动元件（Sk）是杂合的。然而，如果敏感核与杀伤核被包裹在同一个子囊孢子中，敏感核就会存活。因为N.四分孢子通常有两种类型的细胞核，在每一个异型子囊孢子中，可能存在Sk元件，尽管它们不明显。用自然种群的菌株进行的实验将检验这种可能性。(4)一个基因座特异性突变体在N. crassa产生在特定非连锁基因座突变的后代。该行为表明靶基因的重复拷贝与eas突变相关，导致RIP（重复诱导的点突变）。 这一假设正在用RIP缺陷突变体纯合的杂交进行检验。该实验室长期致力于将脉孢菌作为模式生物的发展。 模式生物是科学的巨大财富，因为从它们获得的见解可以用来指导并经常加速对其他相关但不太了解的生物的研究。 该实验室提供的大量遗传和生物学信息使脉孢菌成为比较其他丝状真菌的理想参考生物，包括植物和动物病原体，商业上重要的物种和无数生态上重要的形式。