Genetics of Neurospora

粗糙脉孢菌将被用来研究生命周期有性阶段的基因沉默、发育和细胞生物学。将继续研究减数分裂中未配对的DNA片段中基因的沉默，使用新的绿色荧光蛋白(GFP)标记的基因来确认沉默的普遍性，并确定其开始的时间和持续时间。在巨大的子囊孢子中的基因重新激活后，绿色荧光蛋白将被用来跟踪标记的基因产物离开起源核的运动，其中所有减数分裂产物都存在于共同的细胞质中。沉默的抑制子将被用来探索减数分裂沉默和孢子杀手减数分裂驱动元件灭活敏感的子囊孢子之间的可能关系。平行的研究将调查四种拟同源异种的减数分裂沉默，在这种物种中，子囊的发育被重新编程，以产生四种自育异核产物。其他四种核菌的研究将检查来自自然的菌株是否存在隐蔽的孢子杀手减数分裂驱动元件和有害的隐性突变。由于最近发现的相反交配型染色体之间的结构差异，可能由于最近发现的相反交配型染色体之间的结构差异，四种异花授粉在大多数交配型染色体上被取消。通过渐渗的方法在粗粒核型核型和四种核型核型之间进行交配型染色体的遗传交换，将研究染色体结构差异的来源，并评估它们在四种核型核型的进化中的作用。该实验室继续利用其使用丝状真菌Neuropora的长期经验，探索具有理论和实践意义的基本问题。这项研究有望促进对基因沉默机制的了解(在发育和防御中很重要)，进一步了解基于异核体(同一细胞中的两个遗传不同的核)的遗传系统，并提高脉孢子菌作为参考模式生物的价值，将其与其他丝状真菌进行比较，包括动植物病原体、商业重要物种和无数重要的生态类型。

Neurospora crassa will be used to investigate gene silencing, development, and cell biology during the sexual phase of the life cycle. Studies will continue on the silencing of genes in DNA segments that are unpaired in meiosis, using new green fluorescent protein (GFP)-tagged genes to affirm the generality of silencing and to determine its time of onset and duration. GFP will be used to follow the movement of tagged gene products away from the nucleus of origin following reactivation of genes in giant ascospores where all meiotic products are present in a common cytoplasm. Suppressors of silencing will be used to explore a possible relationship between meiotic silencing and the inactivation of sensitive ascospores by Spore-killer meiotic-drive elements. Parallel studies will investigate meiotic silencing in N. tetrasperma, a pseudohomothallic species in which ascus development is reprogrammed to produce four self-fertile heterokaryotic products. Other N. tetrasperma studies will examine strains from nature for the presence of cryptic Spore killer meiotic drive elements and deleterious recessive mutations. Crossing over in N. tetrasperma is abolished over most of the mating-type chromosome, possibly due to recently discovered structural differences between the chromosomes of opposite mating type. Genetically exchanging mating-type chromosomes between N. crassa and N. tetrasperma, via introgression, will examine the origin of differences in chromosome structure and assess their role in the evolution of the 4-spored condition in N. tetrasperma. The laboratory continues to draw on its long experience using the filamentous fungus Neurospora to explore fundamental problems of theoretical and practical interest. The research is expected to advance knowledge of gene-silencing mechanisms (important in development and defense), to further the understanding of genetic systems that are based on heterokaryons (two genetically different nuclei in the same cell), and to enhance the value of Neurospora as a reference model organism with which to compare other filamentous fungi, including plant and animal pathogens, commercially important species, and innumerable ecologically important forms.