Molecular Analysis of Photoregulated Development

本建议的目的是制定一个详细的 了解光调节的机制 发育基因在A. nidulans。 这样做的目的之一 工作是识别和表征光特异性基因。 的 天鹅绒基因的野生型功能是 光调节发育，但该基因的突变不 干扰分化结构的形成。 这 通过突变体互补和实验， 的表达，并确定其 在野生型和特异性 发育突变体 鹿茸基因的功能分析 通过基因融合的应用将被启动。 额外 光特异性基因已经通过突变被鉴定出来， 通过光暗转换实验进行分析。 方法也是 提出分离新的位点参与光响应。 本项目的另一个目的是鉴定分生孢子特异性 基因需要光来表达， 可能的顺式作用调控序列，控制 这些基因的转录。 光调控的研究 在构巢曲霉分生孢子将有助于阐明 复杂的调节机制， 真核生物的分化，使用高度 进行详细的基因和分子分析。 光是正常生长所必需的， 大多数植物的生长。 植物具有 感知和响应光线， 涉及特定基因的激活。 之甚少 了解这些反应的机制，主要是因为它 只是最近才将分子遗传学分析应用于 植物的这些反应。 该提案的提出者， 在以前的NSF支持期间， 发现光是完成 霉菌构巢曲霉的发育周期，以及 霉菌对光的反应机制 类似于高等植物。 他在这里提出了一个详细的 这种反应的分子遗传学分析。 基因的简单性 操纵模具的承诺迅速和重要的新的 对光反应机制的深入了解。

The objective of this proposal is to develop a detailed understanding of the mechanisms involved in photoregulated developmental gene expression in A. nidulans. One aim of this work is to identify and characterize light-specific genes. The wild-type function of the velvet gene is required for photoregulated development, but mutation of this gene does not interfere with the formation of differentiated structures. This gene has been cloned by mutant complementation and experiments are proposed to characterize its expression and to determine its pattern of transcription in the wild-type and in specific developmental mutants. A functional analysis of the velvet gene through the use of gene fusions will be initiated. Additional light-specific genes have been identified by mutation and will be analyzed by light-dark shifting experiments. Methods are also proposed to isolate novel loci involved in the photoresponse. Another aim of this project is to identify conidiation-specific genes that require light for their expression and to deduce possible cis-acting regulatory sequences that control the transcription of these genes. The study of Photoregulated conidiation in Aspergillus nidulans will help elucidate the complex regulatory mechanisms that affect cellular differentiation in eukaryotes, using an organism that is highly amenable to detailed genetic and molecular analyses. Light is critically required for the normal growth and development of most plants. Plants possess mechanisms for sensing and responding to light, and some of these responses involve the activation of specific genes. Relatively little is known about the mechanisms of these responses, largely because it is only recently that molecular genetic analysis has been applied to these responses in plants. The author of this proposal has, during a period of previous NSF support, made the unexpected discovery that light is critically required for the completion of the developmental cycle of the mold Aspergillus nidulans, and that the mechanism of the mold's response to light appears similar to that of higher plants. He here proposes a detailed molecular genetic analysis of this response. The ease of genetic manipulation of the mold promises rapid and important new insights into the mechanism of light responses.