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Brittany Ripley

Mentor: Todd Washington, PhD

Year Entered Into Program: 2014

Terminal Degree(s) Received and Year: PhD 2020



Research Description

Structure and mechanism of ubiquitin ligase complex Rad6-18 in the activation of TLS

In Dr. M. Todd Washington’s lab, the focus of research is on the proteins and mechanisms involved in the DNA repair process Translesion Synthesis (TLS) which is a process to bypass lesions in the DNA due to damaged bases from radiation or chemicals. Activation of TLS occurs by monoubiquitination of the protein hub, proliferating nuclear cellular antigen (PCNA). My project explores the structure and mechanism of the ubiquitin ligase complex, Rad6-18. To study the ubiquitination process, we are using x-ray crystallography, computational methods, and PCNA ubiquitination assays. 


  • Oral presentation award, Pharmacology / PSET Research Retreat, University of Iowa, 2017
  • Fellowship appointment on the Pharmacological Sciences Training Program (NIH T32 GM067795), University of Iowa, 2016-2017
  • Institutional support on the Pharmacological Sciences Training Program (NIH T32 GM067795), University of Iowa, 2015-2016
  • Center for Biocatalysis and Bioprocessing Training Grant: University of Iowa (declined award)


  1. Ripley, B., Gildenberg, M.S., and Washington, M.T.:  Control of DNA Damage Bypass by Uniquitylation of PCNA. Genes (Basel) Review. 11(2):138, 2020. PMCID: PMC7074500
  2. Ripley, B.M., Reusch, D.T., and Washington, M.T.:  Yeast DNA polymerase η possesses two PIP-like motifs that bind PCNA and Rad6-Rad18 with different specificities. DNA Repair (Amst). 95:102968, 2020. PMID: 32932109