Translation initiation regulation on polycistronic eukaryotic mRNAs

Controlling how cells synthesize proteins from the messenger RNAs (mRNAs) that encode these proteins, a process referred to as protein translation, is essential to normal cell function. Quantitative or qualitative differences in the translation of specific mRNAs influence such diverse events as development and control of cell replication. Alternate mechanisms that regulate the initiation of translation can also result in more than one protein being translated from a single species of mRNA, which has major implications on understanding the complexity of cellular proteomes (i.e. how many different proteins your cells can produce). Mutations that alter the control of translation initiation are also associated with several disease states. Understanding the mechanisms that regulate translation initiation, therefore, has broad implications. Although numerous mechanisms for regulating translation initiation have been described, our understanding of these processes remains far from complete. My research group is exploring this area by analyzing an unusual group of viral mRNAs that encode three different proteins from a single mRNA. These studies hold the promise of defining novel mechanisms that regulate cellular protein synthesis.