Quantification of Folate Content in Solanum lycopersicum × Solanum pimpinellifolium Recombinant Inbred Lines (RILs) for QTL Analysis Using Microbiological Assay
Deficiency of folate and its derivatives (vitamin B9) is a worldwide problem that can impact human health, causing birth defects such as spina bifida, as well as a higher risk of cancer, cardiovascular disease and anemia. Fruits constitute important components of the human diet and contribute a large portion of vitamins, minerals, antioxidants and fiber. All of these fuel the interest for the enhancement of folate content in crops. According to the United States Department of Agriculture, tomato is the second most consumed vegetable in the U.S., but provides roughly 4% of the recommended dietary allowance of folate. The focus of this project is to identify candidate genes affecting folate production using mapping data of a recombinant inbred lines (RILs) population to generate quantitative trait loci (QTLs). Total folate content was determined in 85 lines of a Solanum lycopersicum (NCEBR1) × Solanum pimpinellifolium (LA2093) RIL population using a microbiological assay, utilizing Lactobacillus rhamnosus which requires folate for its growth. We found that the parents of the population show differences in their folate content. S. lycopersicum contains 9.2 µg/100 gFW, while the wild S. pimpinellifolium contains 26.4 µg/100 gFW. Furthermore, in a preliminary LCMS analysis of selected RILs there is a correlation between high folate content and glutamate levels, and between low folate content to glutamine levels. Based on these data, QTLs controlling folate levels will be generated. These QTLs, in conjunction with RNA-seq data, will be used to facilitate the identification of candidate genes governing folate content in tomatoes fruits.
Participating in this program has been an extraordinary experience. I was placed in the Giovannoni lab where I worked alongside amazing mentors who ensured I got the best out of my participation there. The lab environment was very pleasant and kept me motivated throughout the 10 weeks. My mentors provided the right guidance I needed for the project but also allowed me to work independently which boosted my confidence in my ability to conduct research. This internship helped me both fortify my interest in a career in plant sciences as well as further affirm its importance and worldwide contribution, and to finally feel prepared for graduate studies.