Sciences and Mathematics, College of
Biology, Department of
SURS Faculty Advisor
The export of mature mRNA from the nucleus of the cell to the cytoplasm is crucial for a cell’s survival, as this process is necessary to produce proteins encoded by these transcripts. In S. cerevisiae (yeast) cells, a protein known as Mex67 must bind to the mRNA while it’s in the nucleus so it can cross through the nuclear pore complex (NPC). Mex67 cannot bind to the mRNA directly, instead it needs to be accompanied by adaptor proteins to aid it in getting across the NPC. Stress conditions such as heat shock interferes with the function of these adaptor proteins, causing Mex67 to not be able to cross the NPC. However, during heat shock cells induce the production and export of heat shock transcripts that encode proteins that allow for recovery from the stress. One of these transcripts is SSA4, which encodes a protein chaperone that helps cellular proteins refold after denaturation during heat shock. It is unknown what molecular mechanism enables the selective export of SSA4. We hypothesized that there is an unknown adaptor protein that binds to SSA4 so it can recruit Mex67 for export under stress conditions. To test this hypothesis, we first tested various growth conditions in which wild-type yeast cells could grow but mRNA export mutants could not. Following this, an overexpression plasmid library was prepared and will be transformed into this mutant to search for proteins which could rescue this growth defect. We anticipate that this project will aid in identification of adaptors that permit selective mRNA export during cellular stress.
Baker, Chloe and Adams, Rebecca, "Identifying Adaptor Proteins for Selective mRNA Export in S. cerevisiae" (2022). Science University Research Symposium (SURS). 52.