title: Unraveling the molecular basis of temperature-dependent genetic regulation in Penicillium marneffei.
abstract: Penicillium marneffei is an opportunistic fungal pathogen endemic in Southeast Asia, causing lethal systemic infections in immunocompromised patients. P. marneffei grows in a mycelial form at the ambient temperature of 25°C and transitions to a yeast form at 37°C. The ability to alternate between the mycelial and yeast forms at different temperatures, namely, thermal dimorphism, has long been considered critical for the pathogenicity of P. marneffei, yet the underlying genetic mechanisms remain elusive. Here we employed high-throughput sequencing to unravel global transcriptional profiles of P. marneffei PM1 grown at 25 and 37°C. Among ∼11,000 protein-coding genes, 1,447 were overexpressed and 1,414 were underexpressed at 37°C. Counterintuitively, heat-responsive genes, predicted in P. marneffei through sequence comparison, did not tend to be overexpressed at 37°C. These results suggest that P. marneffei may take a distinct strategy of genetic regulation at the elevated temperature; the current knowledge concerning fungal heat response, based on studies of model fungal organisms, may not be applicable to P. marneffei. Our results further showed that the tandem repeat sequences (TRSs) are overrepresented in coding regions of P. marneffei genes, and TRS-containing genes tend to be overexpressed at 37°C. Furthermore, genomic sequences and expression data were integrated to characterize gene clusters, multigene families, and species-specific genes of P. marneffei. In sum, we present an integrated analysis and a comprehensive resource toward a better understanding of temperature-dependent genetic regulation in P. marneffei.
authors.affiliation: Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA.
authors.forename: Ence
authors.initials: E
authors.lastname: Yang
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.forename: Patrick C Y
authors.initials: PC
authors.lastname: Woo
authors.forename: Susanna K P
authors.initials: SK
authors.lastname: Lau
authors.forename: Wang-Ngai
authors.initials: WN
authors.lastname: Chow
authors.forename: Ken T K
authors.initials: KT
authors.lastname: Chong
authors.forename: Herman
authors.initials: H
authors.lastname: Tse
authors.forename: Richard Y T
authors.initials: RY
authors.lastname: Kao
authors.forename: Che-Man
authors.initials: CM
authors.lastname: Chan
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Che
authors.forename: Kwok-Yung
authors.initials: KY
authors.lastname: Yuen
authors.forename: James J
authors.initials: JJ
authors.lastname: Cai
mesh_terms: D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D006360:Heat-Shock Proteins / Q000235:genetics; D018869:Heat-Shock Response / Q000235:genetics*; D006358:Hot Temperature; D010407:Penicillium / Q000235:genetics / Q000378:metabolism*; D020080:Tandem Repeat Sequences; D014158:Transcription, Genetic; D059467:Transcriptome
chemical_list: D006360:Heat-Shock Proteins