Program Book - 27th Fungal Genetics Conference

CONCURRENT SESSION ABSTRACTSprocess, and fatty acid biosynthesis. Complementary analysis using weighted gene co-expression network analysis identified modules with DE genesenriched for transmembrane transport, metabolic process, transcription factor activity, translation, and fatty acid biosynthesis. To identify candidate genesfor ChIP-qPCR, we integrated gene expression microarray data with genome-wide in silico analysis of GATA transcription factor binding motifs. Using thisapproach, we identified a subset of genes bound and regulated by SREB including SIDA, MIRB, WD, HAPX, and PDH at 37 o C and 22 o C. In contrast,enrichment for SREB-3xHA binding of ECI1 occurred at 22 o C, but not 37 o C. In conclusion, integration of microarray analysis, in silico GATA motifs, GOenrichment, and ChIP-qPCR indicates that SREB affects pleiotropic events in B. dermatitidis.Functional Analysis of Genes in Regions of Introgression in Coccidioides. Bridget M. Barker. Immunology & Infectious Diseases, Montana State Univ,Bozeman, MT.Coccidioides immitis and C. posadasii are dimorphic fungi endemic to the Americas. Genomic analysis of sequenced strains of C. posadasii and C. immitisreveals insights into the population biology of these organisms. There is strong evidence for hybridization and introgression, such that for many of the C.immitis strains, there are several regions that have a closer match to C. posadasii, but few regions within C. posadasii matching C. immitis. Multiplehybridization regions were located in several genomes analyzed, and at least one region containing ten genes exhibits a pattern consistent withintrogression in C. immitis. This conserved region was further evaluated in a larger collection of isolates. Approximately half of the C. immitis isolatescontain the C. posadasii fragment, and the majority of those are from the southern California and Mexico populations. The region of introgressionrepresents a unique opportunity to functionally assess genes that are likely to be relevant for species-specific virulence and adaptation to mammalianhosts or the environment. This region has a shared recombination point flanking a metalloproteinase, Mep4; genes that are highly expressed in theparasitic phase; and genes of unknown function. Importantly, evolutionary selection has preserved this region in multiple strains of C. immitis furtheremphasizing the possible role in virulence of these genes. Variation among strains for virulence in murine models of coccidioidomycosis has beenobserved, but has not been tested in the context of the newly discovered species or with a targeted underlying genetic mechanism hypothesis to test.Gene deletion mutants are being generated for three genes in the conserved introgression region to determine effects on in vitro growth andmorphological change under host relevant conditions.27th Fungal Genetics Conference | 99