POX — Hordeum vulgare subsp. vulgare

Summary

HORVU.MOREX.R3.4HG0351880 (HvPOX) on barley chromosome 4H encodes a secretory haem peroxidase (EC 1.11.1.7) with lactoperoxidase, peroxidase, heme-binding and protein-binding activities. The enzyme is associated with hydrogen peroxide catabolism, oxidative stress response, lignin anabolism and activation of syringal lignin synthesis, xylem development, brassinosteroid-mediated signalling, cellular response to hypoxia, and water response. It localises to the apoplast, plant-type cell wall, vacuole, Golgi, mitochondria, cytosol and extracellular space. The gene is linked to grain yield and weight, spike length, grains per spike, biological yield, stem and culm length, root length, chlorophyll content, photosynthetic rate, soluble protein and flavonoid content, proline content, nitrate uptake, ethylene sensitivity, and seedling growth. Associations include resistance to Botrytis cinerea, disease resistance, photoperiod stress response, cell proliferation and leaf development. Studies of related genes in other species connect the family to lignin composition and biosynthesis, salt tolerance, organ size, calcium signalling and protein-protein interactions.