丝状真菌瑞氏木霉纤维素酶基因转录激活模式分子机制的研究

项目名称： 丝状真菌瑞氏木霉纤维素酶基因转录激活模式分子机制的研究

项目编号： No.31270116

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 生物科学

项目作者： 刘巍峰

作者单位： 山东大学

项目金额： 78万元

中文摘要： 真核生物基因转录的精确调控是细胞实现正常生命活动的重要保障。丝状真菌瑞氏木霉在纤维素底物存在的条件下可以迅速地启动纤维素酶基因的高水平转录表达，但其精确的转录调控分子机制并不清楚。本项申请拟利用实验室已经建立的丝状真菌遗传操作平台，针对瑞氏木霉中与纤维素酶基因诱导转录相关的转录调控因子，尤其是围绕重要转录激活因子Xyr1的活性调控机制开展系统研究。在对其DNA结合域和转录激活域在内的结构域功能及作用特点精细解析的基础上，研究分析Xyr1等相关转录调控因子在不同碳源条件下的细胞定位变化及其在特定染色质序列上的动态相互作用模式；结合系列突变株在阻遏和诱导条件下特定启动子序列-蛋白复合物的变化分析，系统阐述Xyr1等转录因子间相互作用及此作用变化对转录活性的影响，从而更深入地揭示丝状真菌纤维素酶基因的表达调控机制，丰富真核生物基因表达调控理论知识，并为将来构建或改良高产纤维素酶菌株提供理论依据。

中文关键词： 瑞氏木霉；转录激活调控；纤维素酶基因；Xyr1；相互作用

英文摘要： Eukaryotic gene expression is a process involving complex interactions among transcription regulators, general transcription factors and chromatin occuring on both a time and a spatial scale. Exquisite regulation of eukaryotic gene transcription is key to assuring its normal life in response to environmental changes. Filamentous fungi represented by Trichoderma reesei can rapidly initiate the launching of cellulase synthesis in the presence of cellulose substrate which otherwise are kept silent. Unfortunately, the precise mechanism underlying this transcription control is not clear yet. The present application aims to carry out systematic study on the relative transcription factors including the essential transcription activator Xyr1 involved in the induced transcription of cellulase genes, to elucidate the mechanisms by which they act concertedly to achieve the regulatory control. In-depth functional characterization of different regions including DNA binding domain and transcriptional activation domain of Xyr1 would be firstly carried out both in vitro and in vivo to understand how different structural regions and other factors act and contribute to its transcriptional activities. By fusing fluorescent protein tags to these factors and taking advantage of bimolecular fluorescence complementation (BiFC) assiste

英文关键词： Trichoderma reesei；regualtion of transcription activation；cellulase gene；Xyr1；interaction