Shotgun proteomics of quinoa seeds reveals chitinases enrichment under
rainfed conditions
Abstract
Quinoa is an Andean crop whose cultivation has been extended to many
different parts of the world in the last decade. It shows a great
capacity for adaptation to diverse climate conditions, including
environmental stressors, and moreover, the seeds are very nutritious in
part due to their high protein content which is rich in essential amino
acids. They also contain good amounts of other nutrients such as
unsaturated fatty acids, vitamins, or minerals and are gluten-free
seeds. Also, the use of quinoa hydrolysates and peptides has been linked
to numerous health benefits. Altogether, these aspects have situated
quinoa as a crop able to contribute to food security worldwide. Aiming
to deepen our understanding of the protein quality and function of
quinoa seeds and how they can vary when this crop is subjected to
water-limiting conditions, a shotgun proteomics analysis was performed
to obtain the proteomes of quinoa seeds harvested from two different
water regimes in field: rainfed and irrigated conditions.
Overrepresented proteins in seeds from each field condition were
analysed, and the enrichment of chitinase-related proteins in seeds
harvested from rainfed conditions was found. These proteins are
described as pathogen-related proteins and can be accumulated under
abiotic stress. Thus, our findings suggest that chitinase-like proteins
in quinoa seeds can be potential biomarkers of drought. Also, this study
points to the need for further research to unveil their role in
conferring tolerance when coping with water-deficient conditions.