Undergraduate education in the biological sciences at Iowa State University is undergoing a dramatic change. Beginning in the 1993-94 academic year, a new core curriculum in biology is being implemented, consisting of two years of integrated instruction for all life sciences majors at Iowa State. A key component of the second year of the biology core will be a genetics and molecular biology laboratory course, which will provide an important opportunity to capture the interest of undergraduates for research opportunities both during their undergraduate careers and beyond. We have designed for this laboratory, a series of challenging, project-oriented exercises that encompass both genetic approaches to mutant characterization and the most advanced methods in molecular biology. The project begins with the isolation of yeast mutants perturbed in pyrimidine metabolism, focusing on the identification of mutants in the uracil biosynthetic gene, URA3. Students will characterize URA3 mutants by complementation analyses, and use molecular methods to clone a wild-type URA3 gene. A computer exercise will initially be conducted to familiarize students with the molecular manipulations carried out in the laboratory. Students will then proceed to amplify a wild-type copy of the URA3 gene from genomic DNA by the polymerase chain reaction, to clone this gene in a plasmid vector that can function both in E. coli and yeast, and to characterize putative recombinants by agarose gel electrophoresis and Southern hybridization analysis. In the final exercise, students will complement their URA3 mutants by transforming them with the cloned, wild-type URA3 gene. The equipment requested provides for growing and transforming yeast, as well as DNA amplification, purification and analysis. Iowa State University will provide an equal match for the funding from the foundation.
