APX — Beta vulgaris subsp. vulgaris

Summary

BvAPX (BVRB_7G179630) on sugar beet chromosome Bvchr7_un.sca010 encodes an L-ascorbate peroxidase (EC 1.11.1.11), a haem peroxidase of the Ccp1-like family. The enzyme is associated with cellular response to oxidative stress, reactive oxygen species homeostasis, and hydrogen peroxide removal. It has been linked to root gravitropism, root angle formation, and auxin metabolism, as well as leaf proximal/distal pattern formation, stomatal development, and the cell cycle G2/M phase transition. Associations with agronomic traits include root yield, root fresh weight, leaf dry weight, net photosynthetic rate, chlorophyll content, starch content, seed viability, days to flowering, and bacterial blight disease resistance. The protein localises to the peroxisome membrane, chloroplast thylakoid membrane, cytosol, and plasmodesmata. Studies of related genes in other species connect the family to drought, heat, salt, and high-light stress tolerance, as well as thermomemory and photoprotection.