Aurelie M. Rafotondrafara, PhD

Assistant Professor of Plant Pathology

The discovery of internal ribosome entry site (IRES) elements in certain RNA messages uncovered a pivotal mechanism of translational regulation in virus infection and in many physiological and pathological stress conditions in eukaryotic cells. Studies of animal viruses have provided major insights into IRES sequences, structures, requirements for host factors and the cellular modifications that the viruses exert to favor their translation. Expanding on these findings, Dr. Rakotondrafara seeks to shed light on the largely unexplored molecular mechanism of internal initiation employed by plant viruses, with the goal of gaining insights into the fundamental processes of protein synthesis employed by uncapped plant RNA viruses that facilitate the development of sustainable virus control based on the disruption of specific viral-host interaction and by testing the durability of widely-deployed resistance based on the disruption of such interactions. They have uncovered a unique and strong IRES element in a recently emergent virus of wheat, triticum mosaic virus, and identified a conserved motif with functional equivalence among plant and animal viruses. Based on the viral requirement for the eukaryotic translation initiation factor 4E, they engineered resistance against potyviruses through the overexpression of a modified eIF4E. The developed resistance resulted not only from the physical disruption of the host factor with the virus but from also an expanded eIF4E regulon genes that seems to activate plant defense response even in the absence of pathogen. Dr. Rakotondrafara collaborates with Dr. Sherer. Dr. Rakotondrafara currently has insufficient grant support to have a trainee in her lab. She will be converted back to full trainer status once that is rectified.