G876L and M674W Transmembrane Mutations Affect Extent of Dimerization in Zebrafish Neuropilins
Advisor: Bryan Berger
Neuropilins are transmembrane proteins composed of two halves, or dimers, that come together to transmit signals across the cell membrane. Successful transduction of this particular pathway results in altered cell motility and plays a role in cancer metastasis and fin regeneration in zebrafish. Mutations in neuropilins disrupt proper dimerization, and thus transduction, due to the change in protein conformation that results from substituting one amino acid for another. Previous work has shown that neuropilins are important for proper signal transduction, but it is still unknown which neuropilin domains are most important. This work investigates the role of the transmembrane portion of neuropilins using site-directed mutagenesis and the AraTM assay. Extent of dimerization was quantified using green fluorescent protein (GFP), where fluorescence was proportional to how effectively the dimers came together. Thus fur, two particularly disruptive mutations have been identified (G876L and M674W) and shown to be statistically significant. These results indicate that the transmembrane domain of neuropilins is important for proper signal transduction. Current and future work addresses mutations in plexins, the neuropilin co-receptor, in order to fully understand how mutations affect cell signaling in zebrafish.
About Megan Kozar:
Megan Kozar joined Lehigh University as a Bioengineering student in 2013, concentrating in Biopharmaceuticals. In her work as an undergraduate research assistant under Dr. Bryan Berger she studied how mutations in membrane proteins called neuropilins affect signal transduction in cells. In January 2015, she received the Clare Luce Boothe Research Scholarship to fund additional research. Megan has participated in a number of internships, including Lehigh Valley Health Network’s Research Scholar Program and Penn State University’s Research Experience for Undergraduates Program, and received support for her research at Lehigh last summer. Megan also serves as a vital member to several organizations on campus such as the Rossin Junior Fellow and Tour Guiding Programs. In her spare time, Megan enjoys running, baking, and traveling. Megan plans to pursue a doctoral degree next year with the ultimate goal of becoming a team leader in the pharmaceutical industry.