Poster abstracts
Poster number 44 submitted by Youssef Hegazy
Mapping of R-loops in yeast cells using DNase H
Youssef A. Hegazy (Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA), Sara C. Cloutier (Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA), Zheng Xing (Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA), Elizabeth J. Tran (1. Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA. 2. Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907, USA)
Abstract:
R-loops are cellular structures composed of an RNA–DNA hybrid and a displaced single-stranded DNA. R loops occur more frequently in the genome and have greater physiological importance than was previously predicted. They play vital roles in regulating gene expression (1), DNA replication (2), and DNA and histone modifications (3). Paradoxically, while they do play essential positive functions required for important biological processes, they can also contribute to DNA damage and genome instability (4). Recent evidence suggests that R-loops are involved in molecular mechanisms of a number of human diseases, including neurological disorders (5) and cancer (4). We are developing a new strategy for mapping R-loops genome wide. This strategy is based on the use of Neisseria meningitidis CRISPR associated protein (NmeCas9) that has been recently shown to have a unique “DNase H” activity (6). We will present progress on establishing this technique to map R-loops in Saccharomyces cerevisiae.
References:
1. Ginno et al. (2013) Genome Res 23: 1590–1600.
2. Xu et al. (1996) EMBO J 15: 3135–3143.
3. Castellano-Pozo et al. (2013) Mol Cell 52: 583–590.
4. Stirling et al. (2012) Genes & Dev 26:163-175.
5. Powell et al. (2013) Proc Natl Acad Sci U S A 110:13938–13943.
6. Zhang et al. (2015) Mol Cell 60:242–255.
Keywords: R-loop , DNase H, S cerevisiae