NSF Postdoctoral Fellowship in Biology FY 2015

This action funds an NSF National Plant Genome Initiative Postdoctoral Research Fellowship in Biology for FY 2015. The fellowship supports a research and training plan in a host laboratory for the Fellow who also presents a plan to broaden participation in biology. The title of the research and training plan for this fellowship to Nathaniel Butler is 'Enhancing genetic map resolution in diploid potato using sequence-specific nucleases.' The host institution for the fellowship is the University of Wisconsin-Madison and the sponsoring scientist is Dr. Shelley Janskey.

Genetic improvement of crops is a vital aspect of agriculture that continues to challenge geneticists and breeders. Over centuries, crops have been domesticated to increase yield, but fully understanding the genetic basis for improving productivity remains an important area of research. A major constraint for finding new traits is that many plant genomes are inherently limited by low rates of recombination, or exchange of DNA, during the fundamental process of sexual reproduction called meiosis. During meiosis, DNA from the male and female mix, break and then recombine in offspring, thus producing the basis for all the variation of life. This project will enhance the ability of plant DNA to recombine more frequently. Rates of recombination will be increased by engineering into potato the enzymes and components necessary for recombination. In turn, mapping of traits will be improved and new variation can be introduced into potato with the potential to greatly enhanced breeding capabilities of crop plants. Through seminars and local activities, high school and undergraduate students will participate in the project and will be trained in the new cutting edge methods of molecular genetics and genome editing.

This project addresses the problem of limited genetic map resolution in bi-parental populations through three objectives. The first objective is to genetically engineer events of diploid potato to express sequence-specific nucleases, TALENs and CRISPR/Cas and a natural nuclease, SPO11 using Agrobacterium-mediated transformation. The second is to evaluate TALEN and SPO11 events using fluorescence in situ hybridization (FISH) and in bi-parental populations using genotyping-by-sequencing (GBS). The third is to map the male fertility (Mf) locus and fine map the pigmented flesh (Pf) locus using CRISPR/Cas events. The results will shed light on the limitations of recombination in a crop species and provide a strategy for improving genetic map resolution. Student involvement will contribute to training the next generation of scientists to learn interdisciplinary approaches in molecular tools.