CAB1 — Cucumis sativus

Summary

CsCAB1 (CSA_3G099680) on cucumber chromosome 3 encodes a chlorophyll a-b binding protein of the light-harvesting complex, possessing chlorophyll binding, xanthophyll binding, pheophytinase, RCC reductase, Chl b reductase, pheophorbide A oxygenase, and chlorophyll b synthesis activities, along with Fe/S binding, histone acetyltransferase, and chitosan/chitin binding functions. The gene is associated with photosynthesis, light harvesting in photosystems I and II, chloroplast thylakoid membrane protein import, response to low light, chlorophyll breakdown, and regulation of programmed cell death and the hypersensitive response. It localizes to thylakoid membranes, photosystems I and II, and the LHCII complex. CsCAB1 is linked to traits including chlorophyll ratio, leaf yellowing tolerance, bacterial blight resistance, net photosynthetic rate, quantum yield, starch and protein content, flowering time, drought and temperature stress responses, stomatal regulation, and leaf senescence. Studies of related genes in other species connect the family to photosystem II function, non-photochemical quenching, state transitions, thylakoid biogenesis, and drought tolerance.