丝状真菌产生的纤维素酶能有效地降解纤维素物质，对于解决能源危机、环境污染和食品短缺等人类面对的严峻挑战具有重要意义。但是，对真菌纤维素酶基因表达调控机制（特别是固态发酵中）研究较少限制了纤维素酶的获得和广泛应用。本实验室获得了固态发酵条件下高产纤维素酶的草酸青霉菌株HP7-1，完成了其基因组测序和遗传操作系统构建。本项目拟以HP7-1为材料，1）通过转录组测定和差异分析，初步确定参与固态发酵中调控纤维素酶基因表达的候选调控基因；2）构建其候选调控基因的缺失突变体和关键调控基因突变体，相应的互补株及高表达菌株，检测纤维素酶活力以验证基因的调控功能；3）通过凝胶阻滞和DNA足迹等实验，确定关键调控因子的直接靶位纤维素酶基因，及所结合的DNA序列。这将首次揭示草酸青霉固态发酵中纤维素酶基因表达的调控机制，对其他丝状真菌固态发酵中纤维素酶基因的调控研究具有理论指导意义和实际应用价值。

Cellulase produced by filamentous fungi can efficiently hydrolyze cellulosic materials, which could help in mitigating serious challenges that mankind faces such as energy crisis, environmental pollution, and food shortage. To date, only limited knowledge has reported on the regulation mechanism of fungal cellulase gene expression, especially under solid-state fermentation. The genome of Penicillium oxalicum HP7-1, a strain that produces high amounts of cellulase under solid-state fermentation, has been sequenced. In addition, a highly efficient gene targeting system that allows rapid genetic manipulation in P. oxalicum HP7-1 has been constructed. In this proposed project, we will deep-sequence and comparatively analyze the transcriptomes of P. oxalicum HP7-1 under different cultivation conditions, and then screen novel candidate regulatory genes involved in the regulation of cellulase gene expression in P. oxalicum HP7-1 under solid-state fermentation. Subsequently, deletion mutants of the candidate genes and complementation of key regulatory gene mutants and their overexpression mutants in P. oxalicum will be established using the constructed gene targeting system, and their cellulase yields will be measured to verify the regulatory roles of the candidate genes. The direct target cellulase genes of the identified regulators and their binding sequences will be determined using electrophoretic mobility shift assay and DNA footprinting. The proposed project will be the first to uncover the regulatory mechanism of cellulase gene expression in P. oxalicum under solid-state fermentation, which will have theoretical and application significances in studying the expression and regulation of cellulase genes in filamentous fungi.