Maize ANT1 modulates vascular development, chloroplast development, photosynthesis, and plant growth

Significance Arabidopsis ANT controls plant growth and floral organogenesis. We determined the binding motif of maize ANT1 (ZmANT1), showing that ZmANT1 binds promoters of milletSCR1 ,GNC , andAN3 , key regulators of Kranz anatomy, chloroplast development, and plant growth, respectively. We generated mutants of theANT1 ortholog in the milletSetaria viridis . Two frameshift mutants displayed reduced photosynthesis efficiency and growth rate, smaller leaves, and lower yields than WT plants. Moreover, their leaves sporadically exhibited distorted vein structure. Transcriptomic comparison of WT and mutant leaves identified down-regulated genes enriched in photosynthesis and tetrapyrrole binding inant1 mutants. Thus, our study identifiedANT1 as a master switch functioning upstream of key regulators of signature developmental processes beyond plant growth and floral organogenesis.