Figure 1

Workflow of the iTRAQ experiments for both the first growth period and grape berry ripening. The first growth period, analyzed in the first iTRAQ experiment, covers four developmental stages: fruit set (FS), 4 mm, 7 mm and 15 mm labeled with the 114, 115, 116 and 117 iTRAQ tags, respectively. The ripening period covers three developmental stages, 100% véraison (V-100), 110 g/l and 140 g/l, and a fourth point, the 15 mm stage, which is common with the previous experiment, and was co-analyzed in a second iTRAQ experiment. For each experiment, the extracted proteins were trypsin-digested and peptides were labeled with iTRAQ tags. After labeling, peptides were pooled and fractionated by strong cation exchange (SCX) chromatography. Each fraction was resolved by reverse phase chromatography and was analyzed directly by mass spectrometry. Searches and quantitation analysis were carried out using the ProteinPilot v1.0 software (Applied Biosystems). Finally, the identified proteins in the set were annotated and functionally analyzed using the Blast2GO v2.4.0 application [43] based on gene ontology (GO) terms.