Gyanendra Singh and Ashok Aiyar
National Institute of Occupational Health, India
LSU Health Sciences Center, USA
Scientific Tracks Abstracts: J Microb Biochem Technol
Epstein-Barr virus (EBV) infects around 95% of human population and its causal association with B-cell lymphomas in children from Sub-Saharan African countries has been established by various epidemiological and molecular studies. Epstein-Barr nuclear antigen 1 (EBNA1), an EBV protein is required for immortalization and transformation of B-cells and results in wide spectrum of diseases that range from infectious mononucleosis to malignancies such as Hodgkin's lymphoma, non-Hodgkin's lymphoma, AIDS related immunoblastic lymphomas, gastric carcinoma, post-transplant lymphomas etc. It is known that transcription activation requires a domain of EBNA1 that binds AT-rich DNA and a second domain termed unique region 1 (UR1) that is conserved in the EBNA1 orthologs of other EBV-like gammaherpesviruses. We have shown in earlier studies that EBNA1's ability to activate transcription is zinc dependent and the two conserved cysteines within UR1 domain are absolutely required for zinc coordination and also respond to the change in the redox microenvironment. We have used bimolecular fluorescence complementation and co-immunoprecipitation techniques to demonstrate that zinc is essential for EBNA1 to transactivate. In addition to zinc regulation, the two critical cysteines within conserved UR1 region are also subject to redox regulation. Oxidative stress conditions are known to cause cysteine oxidation and results in reduced EBNA1's ability to transactivate. We wanted to know whether by over expression of redox proteins such as apurinic/apyrimidinic endonuclease redox effector factor-1 (APE1/Ref-1) modulates EBNA1's ability to transactivate and counteracts the effect of oxidative stress on EBNA1. Our results identify a novel mechanism by which redox regulators modulates EBNA1's ability to transactivate and counteracts the effect of oxidative stress on EBNA1.
Gyanendra Singh has earned his PhD from Central Drug Research Institute and moved to USA for pursuing research in areas of microbiology and molecular biology at LSU Health Sciences Center, New Orleans, LA and K-State University, Manhattan, KS. He is an expert in molecular biology, microbiology and virology that can be seen from his publications (>26) appeared in Journal of Virology, PLoS One, PLoS Pathogens and Journal of Biological Chemistry. Currently he is a Scientist in National Institute of Occupational Health and is also serving as an Editor-In- Chief of the Journal of Metabolomics and Systems Biology as well as Associate Editor of Universal Journal of Biotechnology & Bioinformatics. He has been in the Editorial Board Member of reputed journals.
Email: gyancdri@gmail.com