9604295 Hyman Eukaryotic mRNA 3'-end formation occurs by a complex mechanism involving pre-mRNA cleavage and subsequent enzymatic addition of multiple adenosine residues to create a poly(A) tail. Mutations in RNA sequences that direct polyadenylation also result in defects in termination of transcription suggesting that these two processes may be coupled in an as yet undetermined mechanism. Termination of transcription by RNA polymerase II is most likely a complex process involving one or more accessory factors. This research is aimed at understanding how the mechanisms of mRNA polyadenylation and transcription termination converge to form a functional mRNA 3'-end. A yeast model system will take advantage of combined molecular genetic and biochemical approaches to identify trans-acting factors and corresponding genes required for mRNA 3'-end formation and determine their function. The synthesis of a functional eukaryotic messenger RNA requires the formation of a mature mRNA 3'-end, which occurs by a complex mechanism. Mutations in RNA sequences that direct 3'-end formation also result in defects in the termination of transcription suggesting that the two processes may be coupled in an as yet undetermined mechanism. This research is aimed at understanding the mechanistic relationship between mRNA 3'-end formation and transcription termination in a yeast model system.
