RRR-SOL · Functional Analysis of Recombination-Repair-Replication (RRR) Genes in Solanaceae: Effects on Abiotic Stress Response and Mitochondrial Genome Editing

Organelles like mitochondria and chloroplasts contain their own genomes, yet rely on nuclear-encoded genes for their maintenance. Despite the critical importance of these nuclear-encoded Recombination, Repair, and Replication (RRR) genes for genome stability, their functions in key Solanaceae crops, such as tobacco, potato and tomato, remain largely unknown. This knowledge gap is critical because the RRR genes not only govern plant resilience but may also serve as key modulators for improving the efficiency of mitochondrial gene editing tools like mito-TALENs.Our central hypothesis is that disrupting RRR gene expression destabilizes the organellar genomes, potentially leading to male sterility and increased sensitivity to abiotic stress. Conversely, we hypothesize that modulating these genes can boost the efficiency of mitochondrial genome editing. We will test these hypotheses by characterizing the RRR genes in Solanaceae, generating transgenic lines with altered RRR gene expression, and evaluating the effects on genome integrity, plant fertility, and abiotic stress response. We will also investigate how RRR gene modulation affects the efficiency of mitochondrial gene editing and identify a novel layer of regulation by predicting and validating microRNA candidates. This project will generate a comprehensive catalog of Solanaceae RRR genes, drive the development of potato and tomato lines with cytoplasmic male sterility and enhanced stress resilience, and assess whether modulating these genes can significantly improve mitochondrial genome editing. This fundamental knowledge will provide new tools for crop improvement and contribute to global food security in the context of climate change.