More than meets the eye: Identifying unique carotenoid QTLs in Solanum habrochaites introgression lines
The objective of this project was to use introgression lines (ILs) in the model system tomato, where the wild species S. habrochaites has been introgressed into the background of S. lycopersicum, to identify unique Quantitative Trait Loci (QTLs) containing candidate genes that regulate carotenoid biosynthesis (carotenogenesis). The regulation of this pathway is complex and likely influenced by both biotic and abiotic factors. Carotenoids are large, complex, 40-carbon biological pigments that are found in chloroplasts and chromoplasts and conserved in all plants. Carotenoids aid in the process of photosynthesis and protect plants against free reactive oxygen species during times of stress. Carotenoids are also beneficial to people; they play roles in preventing cancer, heart disease, macular degeneration, supporting the immune system, and more. In order to investigate the mechanisms underlying the regulation of carotenogenesis high pressure liquid chromatography (HPLC) was used for the quantification of different carotenoids present in ripe fruit of each IL. Results were then applied to a genetic map of the ILs created using Single Nucleotide Polymorphisms (SNPs) generated from leaf RNAseq data. Afterwards, unique QTLs were elucidated in regions of the genome with no known carotenoid biosynthetic or regulatory genes present. The underlying genes could be used to create selectively bred crops that are more favorable and nutritionally beneficial. Therefore, a fundamental understanding of the regulation of the biological pathway producing carotenoids is necessary. The goal of this study was to identify novel QTLs in hopes of discovering genes that influence the regulation and synthesis of carotenoids.
My experience with Dr. Giovannoni’s lab group was outstanding. I worked in both the lab and the field, and now better understand the relationship between molecular research and field research. In the lab I was exposure to new research and lab protocols. I had a great mentor who would first guide me through a procedure, but then encouraged me to conduct the procedures on my own. This allowed me to not only make mistakes and learn, but also become more proficient and confident to work in my ability to work independently in the lab. The PGRP program also provided many opportunities to learn about other areas of plant research, ask questions, and learn advanced techniques involved with research, especially bioinformatics. Perhaps the most meaningful thing I learned at BTI is the relevance and importance of plant research in society and how to better prepare for a pathway to graduate school and a research career.