Regulation of infectious spore formation in the fungal pathogen Coccidioides posadasii

SUMMARY The human fungal pathogen Coccidioides causes Valley Fever, a treatment-refractory and sometimes deadly disease prevalent in arid regions of the western hemisphere. Patients contract the disease by inhaling fungal spores from soil. Understanding Coccidioides behavior in the environment is thus key to public health measures for Valley Fever prediction and prevention. We propose a first-ever molecular study of the environmental life cycle of Coccidioides toward this end. Our preliminary work has shown that Coccidioides preferentially makes infectious spores in dry conditions. We now want to know how. We apply experimental- and computational- genomic approaches to dissect desiccation response in Coccidioides outside the host. The rich data sources we generate will pinpoint candidate genes underlying spore formation and will also position us to discover other environmentally-triggered phenotypes in Coccidioides. Our work will open a new wing of the research literature focused on the molecular basis of Coccidioides disease transmission from the environment.