Title: "Functional Characterization of the Nucleobase Cation Symporter 1 in Picea glauca"
Faculty Mentor: Dr. George Mourad (Biology)
External Reviewer: Dr. Vamsi Nalam (Biology)
Honors Program Council Liaison: Dr. James Toole (Political Science)
Laura Trent is a senior at IPFW graduating in May 2014 with a Bachelor of Science degree in Biology and an Associate of Science degree in Chemical Methods. Since coming to IPFW in August 2010, she has been inducted into 3 honors societies and been on the Semester Honors & Dean’s List multiple semesters. She has done research in Dr. Mourad’s laboratory for over a year and also worked part time at a local factory. She plans to work for a year before applying to Parkview Hospital’s Medical Technology internship at the Regional Medical Center. She then plans to continue her education, pursuing a Master’s degree in a field of forensic biology, which she hopes to put into use in a forensic laboratory.
The gymnosperm Picea glauca has the capability to transport purines and pyrimidines as nitrogen sources for various metabolic processes including nucleic acids synthesis, carbodydrate metabolism, and overall plant growth, development and reproduction. The genome of P. glauca contains a single gene that encodes a putative nucleobase cation symporter 1 (PgNCS1). The goal of this work is to identify the solute specificity of PgNCS1 through heterologous expression and radiolabel solute uptake experiments in NCS1-deficient Saccharomyces cerevisiae. Our lab has previously identified the solute specificity of NCS1 from Chlamydomonas reinhardtii and Arabidopsis thaliana using reverse genetics approaches (Schein et al. 2013 and Mourad et al. 2012). The transport properties of PgNCS1 were studied using solute toxic structural analogue growth assays, sole nitrogen source assays, and 3H-nucleobase uptake experiments. The results show that PgNCS1 transports adenine, guanine, uracil, allantoin, xanthine, and hypoxanthine - which shows a similar but not identical substrate specificity to either C. reinhardtii or A. thaliana. This suggests that the plant NCS1 solute transport specificity may not be universal and has undergone important changes through evolutionary history.