Transcriptional profiles of laccase genes in the brown rot fungus Postia placenta MAD-R-698

• Published in: The journal of microbiology Vol. 53; no. 9; pp. 606 - 615
• Main Authors: An, Hongde, Wei, Dongsheng, Xiao, Tingting
• Format: Journal Article
• Language: English
• Published: Seoul The Microbiological Society of Korea 01.09.2015; Springer Nature B.V; 한국미생물학회
• Subjects: Biomedical and Life Sciences; copper; Coriolaceae - classification; Coriolaceae - genetics; Coriolaceae - growth & development; Ethanol; ferulic acid; Fungi; gene expression; Gene Expression Profiling; gene expression regulation; Gene Expression Regulation, Fungal; genes; Genes, Fungal; Genomes; glucose; Hydroxyl radicals; laccase; Laccase - genetics; Life Sciences; Lignin; Lignin - metabolism; lignocellulose; Microbiology; nitrogen; osmotic stress; Oxidation; quantitative polymerase chain reaction; Real-Time Polymerase Chain Reaction; Rhodonia placenta; stress response; transcription (genetics); Transcriptome; Wood - metabolism; Wood - microbiology; 생물학; brown rot fungi; qPCR; laccase; transcriptional regulation
• ISSN: 1225-8873; 1976-3794; 1976-3794
• DOI: 10.1007/s12275-015-4705-4

One of the laccase isoforms in the brown rot fungus Postia placenta is thought to contribute to the production of hydroxyl radicals, which play an important role in lignocellulose degradation. However, the presence of at least two laccase isoforms in this fungus makes it difficult to understand the details of this mechanism. In this study, we systematically investigated the transcriptional patterns of two laccase genes, Pplcc1 and Pplcc2, by quantitative PCR (qPCR) to better understand the mechanism. The qPCR results showed that neither of the two genes was expressed constitutively throughout growth in liquid culture or during the degradation of a woody substrate. Transcription of Pplcc1 was upregulated under nitrogen depletion and in response to a high concentration of copper in liquid culture, and during the initial colonization of intact aspen wafer. However, it was subject to catabolite repression by a high concentration of glucose. Transcription of Pplcc2 was upregulated by stresses caused by ferulic acid, 2, 6-dimethylbenzoic acid, and ethanol, and under osmotic stress in liquid culture. However, the transcription of Pplcc2 was downregulated upon contact with the woody substrate in solid culture. These results indicate that Pplcc1 and Pplcc2 are differentially regulated in liquid and solid cultures. Pplcc1 seems to play the major role in producing hydroxyl radicals and Pplcc2 in the stress response during the degradation of a woody substrate.