XA4 — Oryza sativa Japonica

Summary

OsXA4 (also known as XA4 and OsiWAK1) on rice chromosome 11 encodes a transmembrane receptor protein kinase with serine/threonine kinase activity, calcium ion binding, and steroid and SNARE binding capabilities, belonging to the WAK-like family with EGF-like domains. The gene is associated with cell surface receptor signaling, innate immune response activation, detection of brassinosteroid stimulus, skotomorphogenesis, and pollen recognition and rejection. It is linked to blast disease resistance, defense responses, and salicylic acid signaling, as well as traits including cold tolerance and chlorophyll content. Observed phenotypes for OsiWAK1 include effects on sterility, dwarfism, panicle, root development, anther, and overall growth. The protein localizes to the plasma membrane, endosome, and extracellular side of the plasma membrane. Related genes in other species link the family to non-self recognition and fungal detection.