CesA4 (IRX5) (EC=2.4.1.12) is a catalytic subunit of xylem-specific cellulose synthase enzyme, involved in secondary cell wall biosynthesis - cellulose synthase trerminal complexes. It interacts with CESA7 and CESA8 which is required for a functyional complex and localization in secondary cell wall deposition sites. Expressed in young plants, stems and flowers but not in leaves, roots and shoots. Amounts are increasing as stems mature. Synonymes: Protein IRREGULAR XYLEM 5, IRX5, NWS2.
