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Ryan Baxley


Mentor: Pamela Geyer, Ph.D.
Lab Room: 3159 MERF
Lab Phone: 319-335-7967

Understanding the role of insulator proteins in gene expression during development.

Insulators are specialized DNA sequences that establish independent domains of gene regulation. My research focuses on Suppressor of Hairy-wing [Su(Hw)], a Drosophila zinc-finger DNA binding protein essential for the function of the gypsy insulator. Su(Hw) recruits at least three proteins required for the enhancer blocking and barrier activity of the gypsy insulator. The Drosophila genome contains hundreds of non-gypsy Su(Hw) binding sites (BSs) that share a common DNA recognition motif with the gypsy insulator, but have a distinct architecture. The role of these non-gypsy¬ BSs is largely unknown, with emerging evidence suggesting diverse regulatory functions that depend on genomic context. To understand the role of Su(Hw) in the genome, experiments are underway to determine effects of su(Hw) mutants on nuclear functions. Loss of Su(Hw) results in female sterility, suggesting that Su(Hw) regulates genes critical to ovary development. First, Su(Hw) target genes in the ovary will be identified using gene expression arrays, coupled with chromatin immunoprecipitation studies. Second, we will determine whether proteins required for gypsy insulator function are used for the regulation of ovarian target genes. Third, a genetic screen for new protein interacting partners will be completed. This research will provide a comprehensive understanding of the role of Su(Hw) in genome organization and gene expression.

Publications:

Baxley RM, Geyer PK. The role of insulators in genome organization and gene expression. The Encyclopedia of Life Sciences, John Wiley & Sons, Ltd, 2008.

Soshnev AA, He B, Baxley RM, Jiang N, Hart CM, Tan K, Geyer PK. Genome-wide studies of the multi-zinc finger Drosophila Suppressor of Hairy-wing protein in the ovary. Nucleic Acids Res. 2012 Jul;40(12):5415-31. Epub 2012 Mar 9. PubMed PMID: 22406832; PubMed Central PMCID: PMC3384341.

Baxley RM, Soshnev AA, Koryakov DE, Zhimulev IF, Geyer PK. The role of the Suppressor of Hairy-wing insulator protein in Drosophila oogenesis. Dev Biol. 2011 Aug 15;356(2):398-410. Epub 2011 May 30. PubMed PMID: 21651900; PubMed Central PMCID: PMC3143288.

Abstracts:

Kading ML, Williams EM, Baxley RM, Stein PJ. Substrate preferences of catechol oxidases from sweet potato and potato. American Chemical Society Conference, 2008.

Marion DJ, Soshnev AA, Appleton K, Li, X, Wehling MD, Baxley RM, Geyer PK. Understanding the function of insulators in the Drosophila genome. 49th Annual Drosophila Research Conference, 2008.

Baxley RM, Pinto BS, Geyer PK. Understanding the role of a Drosophila insulator protein in the female germline. University of Iowa Molecular and Cellular Biology Retreat, 2008.

Soshnev AA, Baxley RM, Geyer PK. Understanding the role of a Drosophila insulator protein in the female germline. 50th Annual Drosophila Research Conference, 2009.

Baxley RM, Sosnev AA, Hohl, AM, Klein MW, Liao A, Geyer PK. Elucidating the role of the Drosophila insulator protein in the female germline. 51st Annual Drosophila Research Conference, 2010.

Baxley RM, Klein MW, Gaeth AB, Morales-Rosado JA, Hohl AM, Geyer PK. A genetic screen for mutations affecting the germline function of the Suppressor of Hairy-wing insulator protein. 52nd Annual Drosophila Research Conference, 2011.

Soshnev AA, Baxley RM, Nilson KA, Tan K, He B, Geyer PK. Loss of Suppressor of Hairy-wing protein affects nuclear organization and gene expression during Drosophila oogenesis. 52nd Annual Drosophila Research Conference, 2011.



Honors and Awards

  • MCB Seminar Committee 2011
  • MCB Program Admissions Committee 2009