Matthew Chuff '08 and Robert Wysocki '07 are working on an ongoing project in Professor of Biology Jinnie Garrett's lab this summer. The project examines the AAT1 gene in yeast, which, when mutated, prevents the cells from growing on enriched media. Chuff and Wysocki are building on work done in previous summers in order to determine how the loss of AAT1 function affects cell growth.
Previous students have inserted yeast DNA plasmid libraries, which are small rings of DNA that carry normal yeast genes, into mutant yeast cells. If the mutant yeast cells can now grow on enriched media it is because these cells must have received a functional copy of the AAT1 gene in the plasmid. Before characterizing the plasmid, Chuff and Wysocki must rule out the possibility that the growth on enriched media is not due to a spontaneous reversal of the original mutation. To do this they will remove the plasmids from the yeast cells by using an enzyme called zymolyase to break apart the cell wall, freeing the plasmid from the yeast cell. The plasmid can be replicated efficiently in a bacterial strain, and then inserted into the mutant yeast strain to test the mutant yeast's ability to grow on the enriched media. If the yeast cells can again grow, then the change must be due to the DNA contained in the plasmid.
Chuff and Wysocki can then analyze the particular genes in the plasmid to determine which gene is involved. "So far we've looked at 50 samples, and have 7 good candidates, one with an insert as large as 3,500 base pairs and one as small as 300," explains Chuff. "We hope to be able to sequence some of them by August or next fall, when the department gets its new sequencer," adds Wysocki.
Chuff, a biology major, is an aspiring veterinarian. He is a host of the sports talk radio show on WHCL, Hamilton's radio station. Wysocki, a biochemistry major, will be working on a related project with Professor Garrett for his senior thesis in the upcoming academic year. He is an EMT with HCEMS, as well as a chemistry teacher's assistant and a tutor at the Quantitative Literacy Center.
-- by Laura Trubiano '07
