Optimizing thiamine pyrophosphate metabolism enhances crop yield and quality.

Abstract

Global food security requires sustainable strategies to improve crop yield and nutrition. Although thiamine pyrophosphate (TPP), the active form of vitamin B1, plays a central role in energy metabolism, redox homeostasis, and carbon assimilation, its contribution to crop yield and quality remains largely unexplored. Here, we show that ZmTPK2, a thiamine pyrophosphokinase encoded by the major ear length QTL qKB6.2a, is a key regulator of maize yield. We reveal that ZmTPK2-dependent TPP homeostasis synchronizes three cornerstones of plant metabolism: mitochondrial tricarboxylic acid (TCA) cycle activity, chloroplast-mediated carbon fixation, and nitrogen utilization. Both overexpression and knockout of ZmTPK2 disrupt yield and grain quality, revealing that optimal TPP levels are required for productivity. Exogenous TPP supplementation increases grain yield in maize, rice, and rapeseed up to 9.8%. These findings identify TPP metabolism as a key regulatory pathway for metabolic engineering, biofortification, and global food security solutions.