Unravelling the molecular basis for light modulated cellulase gene expression - the role of photoreceptors in Neurospora crassa

BMC Genomics

Research Article

Jianping Sun¹  N Louise Glass¹  Monika Schmoll²  Chaoguang Tian³  Doris Tisch⁴ 

[1] Plant and Microbial Biology Department, University of California, 94720, Berkeley, CA, USA;Plant and Microbial Biology Department, University of California, 94720, Berkeley, CA, USA;Research Area Gene Technology and Applied Biochemistry, Vienna University of Technology, Getreidemarkt 9, 1060, Wien, Austria;Plant and Microbial Biology Department, University of California, 94720, Berkeley, CA, USA;Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 300308, Tianjin, China;Research Area Gene Technology and Applied Biochemistry, Vienna University of Technology, Getreidemarkt 9, 1060, Wien, Austria;

关键词: Cellulase;    Cellulase Activity;    Cellulolytic Enzyme;    Increase Expression Level;    Cellulolytic Activity;   

DOI  :  10.1186/1471-2164-13-127

 received in 2011-11-21, accepted in 2012-03-31,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundLight represents an important environmental cue, which exerts considerable influence on the metabolism of fungi. Studies with the biotechnological fungal workhorse Trichoderma reesei (Hypocrea jecorina) have revealed an interconnection between transcriptional regulation of cellulolytic enzymes and the light response. Neurospora crassa has been used as a model organism to study light and circadian rhythm biology. We therefore investigated whether light also regulates transcriptional regulation of cellulolytic enzymes in N. crassa.ResultsWe show that the N. crassa photoreceptor genes wc-1, wc-2 and vvd are involved in regulation of cellulase gene expression, indicating that this phenomenon is conserved among filamentous fungi. The negative effect of VVD on production of cellulolytic enzymes is thereby accomplished by its role in photoadaptation and hence its function in White collar complex (WCC) formation. In contrast, the induction of vvd expression by the WCC does not seem to be crucial in this process. Additionally, we found that WC-1 and WC-2 not only act as a complex, but also have individual functions upon growth on cellulose.ConclusionsGenome wide transcriptome analysis of photoreceptor mutants and evaluation of results by analysis of mutant strains identified several candidate genes likely to play a role in light modulated cellulase gene expression. Genes with functions in amino acid metabolism, glycogen metabolism, energy supply and protein folding are enriched among genes with decreased expression levels in the wc-1 and wc-2 mutants. The ability to properly respond to amino acid starvation, i. e. up-regulation of the cross pathway control protein cpc-1, was found to be beneficial for cellulase gene expression. Our results further suggest a contribution of oxidative depolymerization of cellulose to plant cell wall degradation in N. crassa.

【 授权许可】

CC BY   
© Schmoll et al; licensee BioMed Central Ltd. 2012