Molecular Genetics of Conidial Morphogenesis in Neurospora Crassa

真菌为调控生长和发育的细胞过程的分子研究提供了真核模型系统。粗糙脉孢菌和许多其他真菌物种产生无性孢子，称为分生孢子，这是一种重要的传播方式。这项研究的目标是确定这一简单发育过程的分子基础。粗毛拟青霉的分生孢子发育受多个遗传基因的调控，其中绒毛基因的特性最好。预测的绒毛蛋白与Gal4型转录因子具有序列相似性。这项工作的主要目标是表征毛茸茸的功能。这种蓬松的蛋白质有一些区域表明它是一种转录因子。这将得到测试。Flffy作为形态发生调节因子的作用将通过异源启动子的表达来检验。对绒毛诱导基因激活的遗传要求将通过检测分生孢子诱导的基因在发育突变体中的表达来确定。已知的生理变化伴随着发育，代谢状态和发育之间的关系一直是粗毛裸藻研究了30多年的话题。这项拟议的研究结果将使我们更深入地了解粗毛拟青霉是如何调节分生孢子的。营养物质、光照和生物钟都有助于调节分生孢子产生的时间和丰度。阐明分生孢子形成的调控机制将为理解响应不同环境信号的信号转导通路如何共同控制细胞分化提供基础。这项拟议研究的第二个目标是检查生理变化和发育之间的关系。该项目将利用一项新技术，即通过分析微阵列进行转录图谱分析，来评估随着Flaffy表达增加而发生的代谢变化。丝状真菌是一类对社会有巨大影响的生物。真菌在有机物质的腐烂和再循环中起着重要作用。它们也是动植物的重要病原体，用于酶、化学品和药品的工业生产。更好地了解丝状真菌的生理和发育对于控制真菌以提高生产力和人类健康的目标是重要的。该项目将把调节分生孢子形成的分子事件与与真菌的发育和对环境信号的反应有关的生理事件结合起来。

Fungi provide model eukaryotic systems for molecular studies of the cellular processes regulating growth and development. Neurospora crassa and many other fungal species produce asexual spores, called conidia, that are an important means of dispersal. The goal of this research is to define the molecular basis of this simple developmental process. Several genetic loci regulate conidial development in N. crassa and the fluffy gene is the best characterized of these. The predicted fluffy protein has sequence similarity to Gal4-type transcription factors. The primary objective of the work is to characterize the function of fluffy. The fluffy protein has regions suggesting it is a transcription factor. This will be tested. Fluffy's role as a regulator of morphogenesis will be tested by expression of fluffy from a heterologous promoter. The genetic requirements for fluffy-induced gene activation will be determined by examination of conidiation-induced gene expression in developmental mutants. Physiological changes are known to accompany development and the relationship between metabolic state and development has been a topic of interest in N. crassa for over 30 years. The results of the proposed research will provide a deeper understanding of how N. crassa regulates conidiation. Nutrients, light and the circadian clock all contribute to regulation of the timing and abundance of conidia production. Elucidation of the mechanisms that regulate conidiation will provide a foundation for understanding how signal transduction pathways responding to different environmental signals operate together to control cellular differentiation. A second objective of the proposed research is to examine the relationship between physiological changes and development. This project will take advantage of a new technology, transcriptional profiling through analysis of microarrays, to assess the metabolic changes that occur in response to elevated expression of fluffy. Filamentous fungi are a diverse group of organisms with a tremendous impact on society. Fungi play important roles in the decay and recycling of organic material. They are also important pathogens of plants and animals and are used in industrial production of enzymes, chemicals, and pharmaceuticals. A better understanding of the physiology and development of filamentous fungi is important to the goal of manipulating fungi for the purpose of increasing productivity and human health. This project will integrate the molecular events regulating conidiation with physiological events associated with development and responses of fungi to environmental signals.