Functional analysis of Mpk1-mediated cell wall integrity signaling pathway in the thermotolerant methylotrophic yeast Hansenula polymorpha. Functional analysis of Mpk1-mediated cell wall integrity signaling pathway in the thermotolerant methylotrophic yeast Hansenula polymorpha

Purpose: To identify the downstream gene sets regulated by Mpk1p in H. polymorpha under normal and caffeine-treated conditions, we compared the RNA-seq based transcriptional profiles. Methods: Total RNA was isolated according to the hot phenol extraction method and all procedure for RNA sequencing were conducted by ChunLab. More than 1.5-fold regulated genes are functionally classified using the Munich Information Center for Protein Sequences (MIPS) FunCat. Results: Transcriptome analysis of the DL1-L strain revealed that caffeine significantly increased expression of a subset of cell-wall related genes in an Mpk1p-dependent manner, but most of which were not Rlm1-target genes. Conclusion: Our results support the essential role of Mpk1p in maintaining cell wall integrity upon several stress conditions of H. polymorpha. Overall design: mRNA profiles of cells grown at normal and caffeine-treated conditions were generated by RNA-seq using Illumina.