title: McmA-dependent and -independent regulatory systems governing expression of ClrB-regulated cellulase and hemicellulase genes in Aspergillus nidulans.
abstract: Fungal cellulolytic and hemicellulolytic enzymes are promising tools for industrial hydrolysis of cellulosic biomass; however, the regulatory network underlying their production is not well understood. The recent discovery of the transcriptional activators ClrB and McmA in Aspergillus nidulans implied a novel regulatory mechanism driven by their interaction, experimental evidence for which was obtained from transcriptional and DNA-binding analyses in this study. It was found that ClrB was essential for induced expression of all the genes examined in this study, while McmA dependency of their expression was gene-dependent. DNA-binding studies revealed McmA assisted in the recruitment of ClrB to the cellulose-responsive element (CeRE) in the promoters of eglA and eglB, expression of which was significantly reduced in the mcmA mutant. The CCG triplet within the CeRE served as the recognition sequence for the ClrB monomer. In contrast, ClrB did not require McmA for binding as a homodimer to the CGGN8CCG sequences in the promoter of mndB, expression of which was affected less in the mcmA mutant than in all other examined genes. Thus, there are two types of ClrB-mediated regulation: McmA-assisted and McmA-independent. This novel McmA-ClrB synergistic system provides new insights into the complex regulatory network involved in cellulase and hemicellulase production.
authors: Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya-shi, Aichi, 464-8601, Japan.
authors: Nuo
authors: N
authors: Li
authors: Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya-shi, Aichi, 464-8601, Japan.
authors: Emi
authors: E
authors: Kunitake
authors: Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya-shi, Aichi, 464-8601, Japan.
authors: Miki
authors: M
authors: Aoyama
authors: Noda Institute for Scientific Research, 399 Noda, Noda City, Chiba, 278-0037, Japan.
authors: Masahiro
authors: M
authors: Ogawa
authors: Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya-shi, Aichi, 464-8601, Japan.
authors: Kyoko
authors: K
authors: Kanamaru
authors: Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya-shi, Aichi, 464-8601, Japan.
authors: Makoto
authors: M
authors: Kimura
authors: Noda Institute for Scientific Research, 399 Noda, Noda City, Chiba, 278-0037, Japan.
authors: Yasuji
authors: Y
authors: Koyama
authors: Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya-shi, Aichi, 464-8601, Japan.
authors: Tetsuo
authors: T
authors: Kobayashi
mesh_terms: D001233:Aspergillus nidulans / Q000201:enzymology* / Q000235:genetics*; D002480:Cellulase / Q000096:biosynthesis / Q000235:genetics*; D002482:Cellulose / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D006026:Glycoside Hydrolases / Q000096:biosynthesis / Q000235:genetics*; D026161:MADS Domain Proteins / Q000235:genetics / Q000378:metabolism; D064110:Minichromosome Maintenance Proteins / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D015533:Transcriptional Activation
chemical_list: D026161:MADS Domain Proteins; D014157:Transcription Factors; D002482:Cellulose; D006026:Glycoside Hydrolases; C023305:hemicellulase; D002480:Cellulase; D064110:Minichromosome Maintenance Proteins