Margaret Patchin

Mentor: Susan White

Chemistry Department, Bryn Mawr College

A Study of the Stability of L30e Protein

The L30e protein in the eukaryotes Saccharomyces cerevisiae, better known as yeast, is a protein which acts as an autoregulator; it prevents both splicing of the RNA transcript as well as translation. This protein forms a complex with the L30e pre- mRNA and mRNA, and the binding of this protein to the RNA requires presence of a kink turn in the structure of the RNA. The binding of the RNA to the protein involves a few key amino acids in the L30e protein, and changes in the protein have the potential to drastically both the stability of the protein itself as well as its ability to bind to the RNA.

             

After working in lab of couple of weeks already this summer, I plan to study the stability of the L30e protein after being interested in the idea by a previous experiment. Circular dichromism (CD) is a method of analysis that can help determine the secondary structure; CD analysis provides insight into the components of a protein’s secondary structure, and by monitoring changes from structured alpha helices and beta sheets to undstructured in the secondary structure, denaturation can be monitored. Use of this method can shed light on how much a protein mutation changes the structure and behavior of a mutant protein when compared to the wild type. Previous experiments have examined the temperature denaturation of both the wild- type protein and a single mutant, the K28A mutant; however there are two other mutants, F85A and F85W that have not yet been tested in such a manner. Also the testing the initial testing showed that the denaturation was irreversible, and therefore I plan to determine whether or not the denaturation would be reversible if the temperature increase were stopped a lower temperature. I also plan to perform similar experiments with chemical denaturation in the future.