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Title: CgSTE11 mediates cross tolerance to multiple environmental stressors in Candida glabrata

Candida glabratais a human commensal and an opportunistic human fungal pathogen. It is more closely related to the model yeastSaccharomyces cerevisiaethan otherCandida spp. Compared withS.cerevisiae,C.glabrataexhibits higher innate tolerance to various environmental stressors, including hyperthermal stress. Here we investigate the molecular mechanisms ofC.glabrataadaptation to heat stress via adaptive laboratory evolution. We show that all parallel evolved populations readily adapt to hyperthermal challenge (from 47 °C to 50 °C) and exhibit convergence in evolved phenotypes with extensive cross-tolerance to various other environmental stressors such as oxidants, acids, and alcohols. Genome resequencing identified fixation of mutations inCgSTE11in all parallel evolved populations. TheCgSTE11homolog inS.cerevisiaeplays crucial roles in various mitogen-activated protein kinase (MAPK) signaling pathways, but its role is less understood inC.glabrata. Subsequent verification confirmed thatCgSTE11is important in hyperthermal tolerance and the observed extensive cross-tolerance to other environmental stressors. These results support the hypothesis thatCgSTE11mediates cross-talks between MAPK signaling pathways inC.glabratain response to environmental challenges.

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Publication Date:
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Scientific Reports
Nature Publishing Group
Sponsoring Org:
National Science Foundation
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