Characterization of genes regulating meiosis and acrylamide formation in potato

Abstract

Potato (Solanum tuberosum L.) is a globally important staple crop; however, its genetic improvement is constrained by autotetraploidy, high heterozygosity, vegetative propagation, and food safety concerns associated with acrylamide formation during high-temperature processing. This thesis addressed two complementary challenges in potato biotechnology: (i) establishing a foundation for synthetic apomixis to enable clonal seed propagation and stable fixation of elite genotypes, and (ii) reducing acrylamide accumulation in processed tubers through targeted genetic and metabolic interventions. newlineSynthetic apomixis was explored using the MiMe (Mitosis instead of Meiosis) strategy by CRISPR/Cas9-mediated multiplex editing of three key meiotic genes, i.e. SPO11-1, REC8, and OSD1 in S. newlinetuberosum cv. Kufri Jyoti. Bioinformatic analyses confirmed conserved meiotic domains and nuclear localization of the potato homologs. Multiplex CRISPR constructs were developed and introduced via Agrobacterium-mediated transformation. Molecular characterization identified edited lines, notably MiMe_Q, showing disruptions in meiotic gene function and transcriptional suppression indicative of partial conversion toward mitosis-like division, representing an important step toward engineered apomixis . newlineTo mitigate acrylamide formation, precursor pathways were targeted through CRISPR knockdown of StASN and StVInv, and cisgenic overexpression of StGCL to enhance glutathione biosynthesis. Edited ASN and VInv lines showed significant reductions in acrylamide levels in fried tubers (up to ~66.7% and ~58.3%, respectively), while StGCL overexpression resulted in ~58% acrylamide reduction, elevated glutathione content, and improved abiotic stress tolerance. newlineOverall, this work demonstrates an integrated genome-editing framework that advances clonal seed technology and improves food safety in potato, offering a scalable strategy for next-generation potato breeding and processing quality enhancement. newline newline