Discipline: Ecology Environmental and Earth Sciences
Room: Exhibit Hall A
Tyshawn J. Ferrell - Albany State University
Co-Author(s): Meixia Zhao, Department of Biology, Miami University, Oxford, OH, 45056; Damon Lisch, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907
Meiotic recombination is a fundamental process that generates genetic diversity and ensures the accurate segregation of homologous chromosomes. Meiotic recombination is regulated by both genetic and epigenetic factors. While a great deal is known about genetic factors, relatively little is known about epigenetic factors, such as DNA methylation. We hypothesize that the removal of DNA methylation can alter the frequency of recombination. To test this hypothesis, we measured the meiotic recombination in a mutant named maize leafbladeless1 (lbl1), which can prevent the establishment of methylation by inhibiting the biogenesis of trans-acting small short interfering RNAs. In maize, we compared the number of crossovers in F2 families derived from lbl1 mutants and their wild type control siblings using polymorphic genetic markers. We observed no significant changes in the frequency of meiotic recombination in both the euchromatic and heterochromatic regions between the mutant and the wild type plants. We hypothesize that lbl1 may not alter the frequency of meiotic recombination globally, but, rather, may only effect recombination at specific regions of the chromosomes where DNA methylation has been largely reduced in the mutants. We have begun to analyze high throughput small RNA and whole genome bisulfite sequencing data in order to determine the identity of those regions. Our next step will be to develop new markers around those regions, assuming they can be identified. Our research will provide new insights into the understanding of how DNA methylation influence meiotic recombination. References: Lisch, D. (2012). Regulation of transposable elements in maize. Curr. Opin. Plant Biol. 15: 511-516. Cuerda-Gil, D. and Slotkin, R.K. (2016). Non-canonical RNA-directed DNA methylation. Nat Plants 2: 16163. Mirouze, M., Lieberman-Lazarovich, M., Aversano, R., Bucher, E., Nicolet, J., Reinders, J., & Paszkowski, J. (2012). Loss of DNA methylation affects the recombination landscape in Arabidopsis. Proc. Natl. Acad. Sci. USA, 109:, 5880-5885.
Funder Acknowledgement(s): This study was supported by Miami University and Funding was provided by the National Science Foundation Site grant (DBI-1156703) to Dr. Dave Berg and Dr. Ann Rypstra. I would also like to thank the whole Zhao lab for providing technical support.
Faculty Advisor: Meixia Zhao, email@example.com
Role: I have planted the corn samples in the Ecological Research Center (ERC), and eventually harvested their tissue for DNA extraction. I used standard PCR method to amplify the extracted DNA and ran gel electrophorus on the PCR plates. Afterwards I ran the gels through the Gel Doc/Image lab to get a visual of the bans. I also used applications in UNIX to analyze High Throughput sequencing data, which encompasses RNA, DNA, and siRNA production. The only thing I didn?t do was create the polymorphic markers, which were created and given to me by Dr. Zhao.