B1 — Solanum lycopersicum

Summary

SlB1 (SOLYC06G036260.3) on tomato chromosome 6 encodes a beta-carotene 3-hydroxylase, a member of the BETA-OHASE-like and fatty acid hydroxylase families, with iron-binding and hydrolase activities. The enzyme is associated with carotenoid metabolism, including zeaxanthin, lycopene, phytoene, and xanthophyll anabolism, as well as lutein and carotenoid breakdown, vitamin metabolism, and oxidative phosphorylation. It localizes to the chloroplast membrane. SlB1 is associated with fruit color, pericarp color, fruit diameter and size, lycopene and carotene content, xanthophyll and zeaxanthin content, chlorophyll content, sugar content, plant height, stomatal resistance, and drought tolerance. Related genes in other species are linked to altered leaf and seed carotenoid profiles, reduced non-photochemical quenching, and changes in flowering time and abscisic acid biosynthesis.