Sarah Graham Kenan Distinguished Professor, Biochemistry and Biophysics
Area of Interest
We are studying the molecular mechanism of nucleotide excision repair in humans. This is a general DNA repair system that repairs all base lesions including the carcinogenic lesions induced by the main environmental carcinogens sunlight and cigarette smoke. Our lab was the first to reconstitute the excision nuclease in a defined system. Our current work on excision repair aims to understand the structural and kinetic factors that enable the human excision nuclease to remove virtually infinite types of base lesions and to define the interconnections between DNA excision repair, the DNA damage checkpoints, and the circadian clock.
DNA Damage Checkpoints
DNA damage checkpoints are biochemical pathways that transiently block cell cycle progression while the DNA contains damage. Checkpoints prevent genomic instability, cancer, and death in multicellular organisms. The DNA damage checkpoints, like other signal transduction pathways, have four components: damage sensors, mediators, signal transducers and effectors. The goal of our research is to purify the human checkpoint proteins, characterize these proteins biochemically, and reconstitute the DNA damage checkpoint in vitro. We have already established an in vitro system that recapitulates some of the key features of the human DNA damage checkpoint response to base damage. Abnormal checkpoint response to DNA damage is a universal feature of cancers, and biochemical characterization of the checkpoint response should aid in developing new approaches to cancer chemotherapy.
Cryptochrome and Regulation of the Biological Clock
Circadian rhythm is the oscillation in physiology and behavior of organisms with approximately 24-hour periodicity. The circadian clock is synchronized to the daily solar cycle by light. We have discovered that a flavoprotein called cryptochrome, closely related to the light-dependent DNA repair enzyme photolyase, regulates the mammalian circadian clock by light-independent and light-dependent mechanisms. Currently, we are investigating the action mechanism of cryptochrome using biophysical methods including femtochemistry and biochemical methods. In addition, we are investigating the connection between the circadian cycle and DNA repair and how disruption of the circadian cycle might affect the susceptibility of mice and humans to cancers.
Awards and Honors
- Hyman L. Battle Distinguished Cancer Research Award, 2019
- North Carolina Award (the highest civilian honor given by the state), 2016
- Carnegie Corporation’s Immigrant of the Year, 2016
- Norma Berryhill Distinguished Lecture, UNC-Chapel Hill, 2016
- Jupiter Award for Outstanding Contributions to Science Education – Morehead Planetarium and Science Center, 2016
- O. Max Gardner Award, 2016
- ASBMB American Society for Biochemistry & Molecular Biology – Bert and Natalie Vallee Award, 2016
- TACCI Turkish American Chamber of Commerce – Distinguished Service Award, 2016
- TWESCO International Turkish Academy – Gold Medal at UN, 2016
- Ugur Mumcu Memorial – Science Award, 2016
- Lifetime Achievement Health Care Heroes – Triangle Business Journal, 2016
- Nobel Prize for Chemistry, 2015
- Distinguished Visiting Professor – Academia Sinica, 2014
- Distinguished Alumni Award-University of Texas at Dallas, 2009
- Koc Prize, Turkey, 2007
- Honorary Coach of UNC Women’s Basketball Team, 2007
- Honorary Doctorate, Bilkent University, Turkey, 2006
- Member of the National Academy of Sciences, Turkey, 2006
- Member of The National Academy of Sciences, USA, 2005
- Fellow of The American Academy of Arts and Sciences, 2004
News and Stories
Scientists discover surprise anticancer properties of common lab molecule
Aziz Sancar, MD, PhD, and colleagues report that a common molecular tool for DNA labeling also has anticancer properties worthy of further investigation, especially for brain cancers.
Nobel laureate Sancar named recipient of 2019 Hyman L. Battle Distinguished Cancer Research Award
UNC Lineberger's Aziz Sancar, MD, PhD, has been named the 2019 recipient of the Hyman L. Battle Distinguished Cancer Research Award.
Researchers clock DNA’s recovery time after chemotherapy
In the time it takes for an Amazon Prime delivery to arrive, cells damaged by chemotherapy can almost completely fix their most important DNA. That is the case in the livers of mice at least, according to a new study from UNC School of medicine researchers. The lab of Nobel laureate Aziz Sancar, MD, PhD, …