This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2011, Broadening Participation. 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 Mercedita Madison-Villar is "Investigation and implications of gigantism in an animal's genome." The host institution for this fellowship is Colorado State University and the sponsoring scientist is Dr. Rachel Mueller.

Salamanders have genomes that can be eight times bigger than that of humans. The increase is not due to the presence of more genes nor by more copies of genes; it is the result of excess repetitive DNA, possibly derived from transposable elements (TEs). TEs are "genomic invaders" and, throughout evolutionary history, eukaryotic genomes have engaged in an "arms race" with them. Most of the time, the genome wins and maintains its size. However when TEs win, the result can be unchecked proliferation and genome gigantism (GG). Nobel laureate and plant geneticist Barbara McClintock demonstrated that inter-species crosses, known as hybridization, can result in an impaired ability of hybrid genomes to disable TEs, thus providing opportunity for copies to randomly insert themselves. Therefore, one would expect TE proliferation to limit successful hybridization, as newly inserted TEs can disrupt genes and render offspring non-viable. However, plants show this is not always the case. This study investigates what happens in salamanders: is GG in salamanders caused by TEs and does GG reduce the cost of additional TE insertions, thereby permitting frequent hybridization among salamanders' lineages?

Training goals include acquiring genomic, bioinformatics, and computer programming skills. This project broadens participation at the postdoctoral level of a member of a group under-represented in biology who encourages and mentors others who are under-represented.

National Science Foundation (NSF)
Division of Biological Infrastructure (DBI)
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Daniel Marenda
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Madison-Villar Mercedita J
United States
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