Valley Fever

San Joaquin Valley Fever is a human disease caused by the fungus, Coccidioides immitis. This fungus and it’s sister species, Coccidioides posadasii, are found in hot, dry regions from the San Joaquin Valley of California, through Southern California, Arizona, New Mexico, Texas, Mexico, Central America and South America.

Sorghum, drought and fungi

Sorghum (Sorghum bicolor) is a grass closely related to sugarcane (Saccharum) and corn (Zea mays). It is the fifth most important cereal crop globally; its use is increasing due to its ability to resist drought. We are studying the role that fungi play in sorghum’s drought resistance and initiated our studies with the obligately mutualistic mycorrhizal fungi found in sorghum roots, arbuscular mycorrhizal fungi (AM fungi).

Indoor air and water damaged homes

Fungi are found throughout the environment, including the air. Outdoors, there is about one fungal spore per liter and we breathe ca. 11,000 liters of air each day. Outdoors, therefore, you breathe in ca. 11,000 spores each day. Buildings reduce the amount of fungi and, in a well-constructed and maintained building, you would breathe in only ca. 1,100 spores/day. In a water damaged building, where fungi grow on wall board, paper, paint, glue, caulk and wood, the concentration of spores can rise by 10- to 100-fold or more. In these buildings, you could breathe in 110,000 or more spores/day.

Mate Choice in a Microbe? QTL analysis.

Neurospora crassa individuals acting as females in southern India are faced with local suitors from their own species and from a sister species, N. intermedia. Fungi, in general, mate first and then ask if it was a good idea.

Adaptation by Gene Family Expansion or Contraction? Phylogenomics.

The wealth of sequenced fungal genomes has enabled comparative phylogenomics and these comparisons have found that fungi can adapt to new environments by changing the size of gene families. The ancestral state of fungal nutrition is tied to plants, so we compared the genomes of several “green” fungi, those that eat plants, to the genomes of several “red” fungi, those that eat animals.

Introgression, a Major Contributor to Fungal Genetic Variation found by Population Genomics.

Population genomic studies of populations of both Coccidioides species and Neurospora crassa have revealed significant introgression. With Coccidioides, as much as 7% of the genome of C. immis can be traced to its sister species, C. posadasii [Neafsey et al. 2010] and one of the introgressed regions has the hallmarks of a selective sweep indicating that at least one of the genes in the region could be important to adaptation [Whiston et al. 2012]. Population genomics of N. crassa found two, recently diverged populations each with two more recently introgressed regions.