Nucleic acid-guided genome editing of plant carbohydrate pathways for functional crops supporting glycogen...

Nucleic acid-guided genome editing is transforming plant breeding by enabling precise modification of metabolic pathways to meet evolving food and nutritional needs. In this study, we applied multiplex CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats and CRISPR-associated protein 9) editing to improve Ipomoea batatas (sweet potato), a climate-resilient staple, for enhanced starch yield and customized digestibility suited for athletic performance nutrition. We targeted four key starch-related genes: AGPase (ADP-glucose pyrophosphorylase), GBSSI (granule-bound starch synthase I), SBEII (starch branching enzyme II), and GPT1 (glucose-6-phosphate translocator). Editing efficiency reached 85 to 92 % across multiple genome copies (homeologs), with no detectable off-target effects. The edited lines showed up to a 20 % increase in total starch and a fivefold reduction in amylose, which is the slowly digestible fraction of starch. This resulted in a high-amylopectin profile associated with rapid glucose release. Transcriptome analysis confirmed the metabolic shifts, including increased expression of GPT1 and sucrose synthase and reduced expression of invertase, which supports improved carbon allocation toward starch biosynthesis. In vitro digestibility and glycemic index (GI) assessments confirmed the functional impact of these traits for glycogen replenishment. Yield performance and drought resilience were retained, confirming agronomic viability. This study highlights the potential of CRISPR-based editing to develop climate-smart, nutritionally functional crops for both health-focused applications and global food security.