Protein kinase C regulates the expression of cell wall-related genes in RlmA-dependent and independent manners in <i>Aspergillus nidulans</i>

A protein kinase C of <i>Aspergillus nidulans</i>, PkcA, is required for cell wall integrity (CWI) and is considered a major component of the regulating pathway. To investigate whether PkcA regulates the transcription of cell wall-related genes, we constructed strains expressing <i>pkcA</i>(R429A) that encodes an activated form of PkcA. The mRNA levels of most chitin synthase genes and an α-glucan synthase gene, <i>agsB</i>, were increased when <i>pkcA</i>(R429A) expression was induced. These mRNA increases were not observed or were only partially observed, in a deletion mutant of <i>rlmA</i>, an ortholog of <i>RLM1</i> that encodes a transcription factor in the CWI pathway in <i>Saccharomyces cerevisiae</i>. In addition, in a <i>pkcA</i> temperature-sensitive mutant under heat stress, the mRNA levels of some chitin synthase genes and <i>agsB</i> did not increase. These results suggest that PkcA is involved in CWI maintenance through the transcriptional regulation of cell wall-related genes.