In-Depth Shotgun Proteomic Characterization of Chickpea (Cicer arietinumL.): A Case Study on the Genotype Pascià Grown Using Two Water Regimes

In the last two decades, chickpea has drawn increasing attention due to its low production cost, high content of proteins with good biological value, a well-balanced amino acid profile, and potential health benefits. To date, almost all studies about chickpea seed proteins have been performed using gel-based approaches and large-size databases (e.g., the taxonomy Viridiplantae). In the present study, a shotgun approach was employed to explore the chickpea seed proteome. To this aim, the genotype Pascià, grown under two water regimes, was used as a case study. Due to the combination of high resolution and high mass accuracy of mass spectral data, along with the use of a database restricted only to Cicer arietinum entries (reviewed and unreviewed) downloaded from the UniProt database (updated February 2023, 31239 entries), it was possible to enlarge the actual knowledge of the seed chickpea proteome by identifying more than 700 novel proteins previously undetected. This analytical approach, also including a label-free quantification (LFQ), was applied to compare two chickpea samples of the genotype Pascià, grown in an open field under two different water regimes, namely rainfed and irrigated. The results of this comparison allowed us to explore the plant’s response to the two different water regimes applied in this study .