SBE1 — Zea mays

Summary

ZM00001EB242610, designated ZmSBE3 (synonyms SBE1, SBEIIB, SBE3) on maize chromosome 5, encodes a Q-enzyme with 1,4-alpha-glucan branching enzyme activity (EC 2.4.1.18) and isoamylase activity, belonging to the glycoside hydrolase 13 superfamily. The gene is associated with amylopectin and starch biosynthesis, carbohydrate storage, amyloplast organization, and anaerobic respiration. It has been linked to numerous grain and endosperm traits including amylopectin and amylose content, starch concentration and digestibility, grain dry weight, seed weight, grain width, flour particle size, sugary and dull endosperm phenotypes, and starch gelatinization temperature. Additional associations include leaf weight, specific leaf weight, ear weight, root weight, coleoptile length, seedling vigor, net photosynthetic rate, transpiration rate, relative growth rate, nitrogen content, heterosis, and grain filling period. Studies of related genes in other species connect the family to grain texture, bread loaf volume, and amylose-to-amylopectin ratio.