Experimental design. Soluble and membrane-bound proteins were extracted from juice sac cells from at least 20 fruits at three stages of Citrus fruit development (early Stage II, Stage II and Stage III) and pooled at each stage. Five technical repeats of each pooled sample (older vs younger fruit) were each analyzed by SIEVE using blanks (washes) between each sample run. Comparisons were conducted in pairs in the following: Stage II vs. early Stage II and stage III vs. Stage II. Methods as described in Experimental Procedures.