Fungal Genetics

Catalog description

Fungal breeding systems, mating types, asexual restrictions and recombination, tetrad analysis, gene conversion and extra genetic elements. PPATH 544 Fungal Genetics (4) Fungal genetics will focus on the classical genetics of fungi starting with the expected inheritance ratios and patterns for single gene and multiple genes on various fungal traits. The methods of establishing crosses and obtaining progeny will be covered in the examples provided. Mating type and breeding systems are an important trait for obtaining the sexual phase, therefore an emphasis will be placed on the genetic determination of breeding methods and mating type, and what is known of mating type switching. There are several unique phenotypes associated only with fungi (pokey, senescent fungi, killer character and others) inherited by mitochondrial DNA and induced by plasmids or transposons. The determination of inheritance and the importance will be examined. Fungi provide the unique opportunity to conduct tetrad analysis in determination of inheritance and mapping of traits. In the laboratory, crosses will be set up by students to obtain data to conduct tetrad analysis and to visualize unusual tetrads brought about by gene conversion. Exchange of genetic material occurs without the sexual cycle though heterokaryosis and the parasexual cycle but may be limited by vegetative incompatibility. These difficult concepts will be discussed as well as visualized by conducting experiments in the laboratory. In discussions, an emphasis will be placed on plant pathogenic fungi and inheritance of virulence which is an important plant pathogen trait. Finally topics on population genetics of fungi including determination of genetic diversity, allele frequencies, genotype frequencies will be studied. Evaluation of student performance will be based on problems sets provided throughout the semester, laboratory reports, student projects and presentations, and a final examination. The problem sets are designed to help students solve genetic problems based on the concepts learned in lecture. The laboratory experiments are designed to complement the lectures and allow students to visualize difficult concepts from lecture. Students will be assigned a plant pathogenic fungus and will explore the literature especially any relevant genetic information on that fungus. The final examination will focus on short answer questions requiring the student to synthesize information. The course will be offered every other spring semester even years. Expected enrollment is 10 students.