Prevalent protein abundance and characteristic peptides in the seed proteome of basmati rice (Oryza sativa L.)

In the changing climatic scenario, the application of proteomics for accelerated identification of elite genes is an important way to speed up the development of elite lines. Seeds, the reservoir of protein expression in most aspects of plant development, are an attractive platform for identifying unique/novel proteins. There has been no report on the seed proteome of basmati rice (Oryza sativa L.). This study presents, for the first time, the seed proteome of superior Indian basmati rice varieties Pusa Basmati 1121 and Pusa Basmati 1718, which are important genetic resources in basmati rice breeding. Through label-free quantitative proteomics, a new source of genes was identified by exploiting the predominant protein abundance and unique peptides. The protein hub related to flowering time revealed a probable photoperiod-independent pathway in Pusa Basmati 1121 with an abundant expression of the Photoperiod Independent Flowering Gene 1 protein. Pusa Basmati 1121 and 1718 contained proteins related to ABA synthesis and biotic and abiotic tolerance, respectively. The signature peptides of thaumatin-like protein and a plant antimicrobial protein from Pusa Basmati 1718 are a new addition to the plant antimicrobial peptides from basmati rice. The primary structure analysis of seed proteins indicated the lysine status, while the abundant non-starch glucans sent clues for targeted research on these basmati rice varieties as a therapeutic food.