Genetics of Neurospora

粗神经孢子虫将用于研究生命周期有性阶段的基因沉默、发育和细胞生物学。今后将继续研究减数分裂中未配对DNA片段中基因的沉默，使用新的绿色荧光蛋白（GFP）标记基因来确认沉默的普遍性，并确定沉默的发生时间和持续时间。在巨大子囊孢子中，所有减数分裂产物都存在于一个共同的细胞质中，GFP将用于跟踪标记的基因产物在基因再激活后离开起源细胞核的运动。沉默抑制子将用于探索减数分裂沉默与孢子杀手减数分裂驱动元件使敏感子囊孢子失活之间的可能关系。平行的研究将调查四asperma的减数分裂沉默，这是一种假同源物种，其中子囊发育被重新编程以产生四种自育异核产物。其他的四asperma研究将检查来自自然界的菌株是否存在隐孢子杀手减数分裂驱动元件和有害的隐性突变。在四asperma中，大多数交配型染色体上的杂交被取消，可能是由于最近发现的相反交配型染色体之间的结构差异。通过基因渐渗，在草稻和四丝稻之间交换交配型染色体，将检验染色体结构差异的起源，并评估它们在四丝稻4孢子条件进化中的作用。实验室继续利用其长期使用丝状真菌神经孢子菌的经验来探索理论和实践兴趣的基本问题。该研究有望促进对基因沉默机制（在发育和防御中很重要）的认识，进一步了解基于异核体（同一细胞中两个遗传不同的细胞核）的遗传系统，并提高神经孢子虫作为参考模式生物的价值，与其他丝状真菌进行比较，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。

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.