Transcription factor FfMYB15 regulates the expression of cellulase gene FfCEL6B during mycelial growth of Flammulina filiformis

• Published in: Microbial cell factories Vol. 21; no. 1; pp. 1 - 216
• Main Authors: Liu, Zongqi, Deng, Bing, Yuan, Hui, Zhang, Benfeng, Liu, Jingyu, Meng, Junlong, Chang, Mingchang
• Format: Journal Article
• Language: English
• Published: London BioMed Central Ltd 17-10-2022; BioMed Central; BMC
• Subjects: Biodegradation; Cellulase; Cellulose; Cellulose degradation; Chemical properties; Cloning; Correlation coefficient; Correlation coefficients; Degradation; Electrophoretic mobility; Flammulina filiformis; Fungi; Gene expression; Genetic aspects; Genomes; Growth rate; Localization; Microbiological research; Molecular weight; Mushrooms; Mushrooms, Edible; MYB; Mycelia; Phylogenetics; Physiological aspects; Regulatory mechanisms (biology); RNA-mediated interference; Transcription factors; Transcriptional regulation; China
• ISSN: 1475-2859; 1475-2859
• DOI: 10.1186/s12934-022-01932-z

Cellulose degradation can determine mycelial growth rate and affect yield during the growth of Flammulina filiformis. The degradation of cellulose requires the joint action of a variety of cellulases, and some cellulase-related genes have been detected in mushrooms. However, little is known about the transcriptional regulatory mechanisms of cellulose degradation. In this study, FfMYB15 that may regulate the expression of cellulase gene FfCEL6B in F. filiformis was identified. RNA interference (RNAi) showed that FfCEL6B positively regulated mycelial growth. Gene expression analyses indicated that the expression patterns of FfCEL6B and FfMYB15 in mycelia cultured on the 0.9% cellulose medium for different times were similar with a correlation coefficient of 0.953. Subcellular localization and transcriptional activity analyses implied that FfMYB15 was located in the nucleus and was a transcriptional activator. Electrophoretic mobility shift assay (EMSA) and dual-luciferase assays demonstrated that FfMYB15 could bind and activate FfCEL6B promoter by recognizing MYB cis-acting element. This study indicated that FfCEL6B played an active role in mycelial growth of F. filiformis and was regulated by FfMYB15.