iTRAQ-based protein profiling provides insights into the central metabolism changes driving grape berry development and ripening

Abstract

BackgroundGrapevine (Vitis vinifera L.) is an economically important fruit crop. Quality-determining grape components such as sugars, acids, flavors, anthocyanins, tannins, etc., accumulate in the different grape berry development stages. Thus, correlating the proteomic profiles with the biochemical and physiological changes occurring in grape is of paramount importance to advance in our understanding of berry development and ripening processes.ResultsWe report the developmental analysis of Vitis vinifera cv. Muscat Hamburg berries at the protein level from fruit set to full ripening. An iTRAQ-based bottom-up proteomic approach followed by tandem mass spectrometry led to the identification and quantitation of 411 and 630 proteins in the green and ripening phases, respectively. Two key points in development relating to changes in protein level were detected: end of the first growth period (7 mm-to-15 mm) and onset of ripening (15 mm-to-V100, V100-to-110). A functional analysis was performed using the Blast2GO software based on the enrichment of GO terms during berry growth.ConclusionsThe study of the proteome contributes to decipher the biological processes and metabolic pathways involved in the development and quality traits of fruit and its derived products. These findings lie mainly in metabolism and storage of sugars and malate, energy-related pathways such as respiration, photosynthesis and fermentation, and the synthesis of polyphenolics as major secondary metabolites in grape berry. In addition, some key steps in carbohydrate and malate metabolism have been identified in this study, i.e., PFP-PFK or SuSy-INV switches among others, which may influence the final sugar and acid balance in ripe fruit. In conclusion, some proteins not reported to date have been detected to be deregulated in specific tissues and developmental stages, leading to formulate new hypotheses on the metabolic processes underlying grape berry development. These results open up new lines to decipher the processes controlling grape berry development and ripening.

A Deep Proteomics Perspective Into Grape Berry Quality Traits During Ripening

“…While two proteins from the mevalonate pathway destined to the terpenoid backbone formation (isopentenyl diphosphate isomerase and 4‐hydroxy‐3‐methylbut‐2‐enyl diphosphate) were quantified, the downstream acting enzymes responsible for the synthesis of monoterpenes were barely detected. The same phenomenon is also observed in other biochemical pathways of the SM responsible for the biosynthesis of other important metabolites from a wine quality perspective such as the polyphenols, non‐flavonoids hydroxycinnamic acids (CAD), and the flavonoids anthocyanin (ANR, ANS) and proanthocyanidins (CHS, CHI, F3H) . The most frequently identified proteins (shown within brackets) belong to the early or mid‐pathway and the common central pathway of the phenylpropanoids (PAL).…”

“…The authors reported on proteins involved in the production of monoterpenes, volatile fatty acid derivatives, phenylpropanoids, benzenoid volatiles, and methoxypyrazines. Few proteomic studies have shown protein profiles regarding proteins involved in the production of aroma and flavor, [3] either because these proteins were not identified, or it was not in the scope of the investigation. To date there are only two publications that have focused entirely on the study of the profiles of proteins in ripening involved in the production of aroma and flavor volatiles in the grapes of two different varieties.…”

“…The same phenomenon is also observed in other biochemical pathways of the SM responsible for the biosynthesis of other important metabolites from a wine quality perspective such as the polyphenols, non-flavonoids hydroxycinnamic acids (CAD), and the flavonoids anthocyanin (ANR, ANS) and proanthocyanidins (CHS, CHI, F3H). [3,6] The most frequently identified proteins (shown within brackets) belong to the early or mid-pathway and the common central pathway of the phenylpropanoids (PAL). The main reasons are the lack of knowledge about the acting enzymes which is reflected in the public databases and the lack of sufficient proteome coverage which is commonly obtained by the discovery-based hypothesis-free proteomics experiments.…”

Functional and Integrative Analysis of the Proteomic Profile of Radish Root under Pb Exposure

“…Isobaric tags for relative and absolute quantification (iTRAQ) is a robust mass spectrometry of protein quantitative technology, which can perform relative and absolute quantification in up to eight samples in parallel (Bindschedler and Cramer, 2011; Glibert et al, 2014). Recently, iTRAQ has been widely used for large-scale quantitative plant proteomic studies in exploration of various metabolic processes at the post-transcriptional level (Kambiranda et al, 2013; Martínez-Esteso et al, 2013) in response to various stresses (Yang et al, 2014; Li et al, 2015; Fu et al, 2016). Additionally, iTRAQ-based proteomics has been proven as a powerful method for unraveling the molecular regulatory networks involved in interactions between heavy metals and plant species, and a set of HM-responsive candidate proteins have been successfully identified.…”

Ampelographic description of cluster, berry and seed of merlot cultivar (Vitis vinifera L.) and its selected clones

“…Today, it is cultivated in all temperate regions of the world. Considered as the most important fruit crop in the world, it plays an important role in the economy of many developed and emerging countries (Martínez-Esteso et al, 2013). Merlot is one of the most important grape cultivars in the wine industry.…”