John J. Wyrick, Ph.D.
School of Molecular Biosciences
Washington State University
Pullman, WA 99164-7520
We are investigating how DNA damage is formed and repaired in chromatin on a genome-wide scale, and how damage formation and repair influences subsequent mutagenesis. Our focus has been on UV-induced DNA damage, which is primarily repaired by nucleotide excision repair (NER) pathway. We are also studying how nucleosome positioning and histone modifications regulate the repair of DNA base lesions throughout the genome. To advance these studies, we have developed novel genomic tools to map DNA lesions at single-nucleotide resolution throughout the yeast and human genomes.
Our group is also researching how chromatin impacts CRISPR-Cas9 genome editing. We have shown that nucleosomes significantly inhibit Cas9 endonuclease activity when the associate PAM site is located within a strongly positioned nucleosome, but are permissible for Cas9 cleavage when the PAM site is in accessible linker DNA. We are currently investigating the impact of chromatin on higher fidelity Cas9 variants and on Cas9 off-target activity.
1. Mao, P., Brown, A.J., Malc, E.P., Mieczkowski, P.A., Smerdon, M.J., Roberts, S.A., and Wyrick, J.J. (2017) Genome-wide maps of alkylation damage, repair, and mutagenesis in yeast reveal mechanisms of mutational heterogeneity. Genome Res. 27:1674-1684.
2. Mao, P., Wyrick, J.J., Roberts, S.A., and Smerdon, M.J. (2017) UV-Induced DNA Damage and Mutagenesis in Chromatin. Photochem Photobiol. 93:216-228.
3. Mao, P. and Wyrick, J. J. (2017) Emerging Roles for Histone Modifications in DNA Excision Repair. FEMS Yeast Research (in press).
4. Hinz, J.M., Laughery, M.F., and Wyrick, J.J. (2016) Nucleosomes Selectively Inhibit Cas9 Off-target Activity at a Site Located at the Nucleosome Edge. J Biol Chem 291:24851-24856.
5. Kong, M., Liu, L., Chen, X., Driscoll, K.I., Mao, P., Bohm, S., Kad, N.M., Watkins, S.C., Bernstein, K.A., Wyrick, J.J., Min, J.H., and Van Houten, B. (2016) Single-molecule imaging reveals that Rad4 (XPC) employs a dynamic DNA damage recognition process. Molecular Cell 64:376-387.
6. Mao, P., Smerdon, M.J., Roberts, S.A., and Wyrick, J.J. (2016) Chromosomal landscape of UV damage formation and repair at single-nucleotide resolution. Proc Natl Acad Sci USA 113:9057-9062.
7. Mao, P., Kyriss, M. N. M., Hodges, A. J., Duan, M., Morris, R. T., Lavine, M. D., Topping, T. B., Gloss, L. M., and Wyrick, J. J. (2016) A Basic Domain in the Histone H2B N-terminal Tail is Important for Nucleosome Assembly by FACT. Nucleic Acids Res. 44:9142-9152.
7. Hinz, J.M., Laughery, M.F., and Wyrick, J.J. (2015) Nucleosomes Inhibit Cas9 Endonuclease Activity in Vitro. Biochemistry 54:7063-7066.