Proteomics Reveals Distinct Changes Associated with Increased Gamma Radiation Resistance in the Black Yeast Exophiala dermatitidis

• Published in: Genes Vol. 11; no. 10; p. 1128
• Main Authors: Schultzhaus, Zachary S, Schultzhaus, Janna N, Romsdahl, Jillian, Chen, Amy, Hervey Iv, W Judson, Leary, Dagmar H, Wang, Zheng
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 25-09-2020; MDPI
• Subjects: Cell cycle; Deoxyribonucleic acid; DNA; DNA biosynthesis; DNA damage; DNA repair; DNA, Fungal - analysis; DNA, Fungal - genetics; Exophiala; Exophiala - genetics; Exophiala - growth & development; Exophiala - metabolism; Exophiala - radiation effects; Fungal Proteins - genetics; Fungal Proteins - metabolism; Gamma Rays - adverse effects; Gene Expression Regulation, Fungal - radiation effects; Genomes; Homologous recombination; Melanins - metabolism; Oxidative stress; Phenotypes; Proteins; Proteome - analysis; Proteome - metabolism; Proteomes; Proteomics; Radiation; Radiation Tolerance; Transcriptome - radiation effects; γ Radiation; translation; proteomics; radiobiology; black yeast; melanin
• ISSN: 2073-4425; 2073-4425
• DOI: 10.3390/genes11101128

The yeast
exhibits high resistance to γ-radiation in comparison to many other fungi. Several aspects of this phenotype have been characterized, including its dependence on homologous recombination for the repair of radiation-induced DNA damage, and the transcriptomic response invoked by acute γ-radiation exposure in this organism. However, these findings have yet to identify unique γ-radiation exposure survival strategies-many genes that are induced by γ-radiation exposure do not appear to be important for recovery, and the homologous recombination machinery of this organism is not unique compared to more sensitive species. To identify features associated with γ-radiation resistance, here we characterized the proteomes of two
strains-the wild type and a hyper-resistant strain developed through adaptive laboratory evolution-before and after γ-radiation exposure. The results demonstrate that protein intensities do not change substantially in response to this stress. Rather, the increased resistance exhibited by the evolved strain may be due in part to increased basal levels of single-stranded binding proteins and a large increase in ribosomal content, possibly allowing for a more robust, induced response during recovery. This experiment provides evidence enabling us to focus on DNA replication, protein production, and ribosome levels for further studies into the mechanism of γ-radiation resistance in
and other fungi.