Figure 4.

Expression and processing kinetics of citrus Chlase during ethylene-induced fruit color-break. Mature green lemon fruit were treated with ethylene (20 μL L⁻¹) at 25°C in the dark for 0, 12, 24, 48, 72, or 120 h in a 600-L sealed container. The container was ventilated once every 24 h, followed by injection of fresh ethylene, to maintain CO₂ levels below 1%. The flavedo of the treated and control fruit was peeled, frozen in liquid nitrogen, and ground to a powder. A, Total protein from each time point was acetone precipitated, extracted in USB protein extraction buffer, separated by SDS-PAGE (30 μg protein/lane), blotted, and dressed with anti-citrus Chlase antibodies. Protein bands bound by the Chlase-specific antibodies were visualized by chemiluminescence. Relative molecular weights of the bands detected by the antibody are denoted. B, Representative lemon fruit phenotype was documented for each time point of ethylene treatment.