Análise proteômica de sementes em desenvolvimento de açaí (Euterpe oleracea Mart)

Abstract

Açaí (Euterpe oleracea Mart) belongs to the family Arecaceae and its economic importance is centered mainly on fruit harvesting for pulp production. In recent years, the demand for açaí pulp increased significantly, mainly due to the functional appeal. However, most of the harvest corresponds to the seed, normally discarded as waste during the production process, once there are no viable alternatives for its use on a large scale. Considering such problem, it is understood that basic studies, can provide subsidies capable of improving seed use. In this perspective, a label-free proteomic analysis of E. oleracea seed was carried out at four developmental stages, designated E3, E6, E9 and E11, which resulted in the identification of 758, 897, 285 and 69 proteins respectively, and a total of 1,080 proteins. The functional categorization of these proteins, showed that most of them integrated the classes of carbohydrate metabolism, amino acid metabolism, protein synthesis, cell wall, secondary metabolism, lipid metabolism, transporters and EROS metabolism. Already, in the relative quantification using precursor ion intensity, 21, 43, 14, 37, 14 and 3 proteins were identified as differentially expressed by the test t (p ˂ 0,05), in the contrasts E6/E3, E9/E3, E11/E3, E9/E6, E11/E6 and E11/E9, respectively. Proteins with similar expression pattern were grouped into six distinct groups. The relative abundance of the enzymes sucrose synthase, UTP-glucose-1-phosphate-uridyl transferase, α-galactosidase, mannose-1-phosphate guanyliltranferase and peroxidase 72 was increased at E6, suggesting that at this developmental stage both deposition and modification of cell wall polysaccharides and indicates the formation of polysaccharides based on mannose, which should constitute the hemicellulosic fraction. Storage proteins type 63 KDa globulin like protein and 7S globulin were accumulated in seed until maturity starting at E6. These proteomic analysis the seed in development of açaí, focusing on some aspects of cell wall formation, since it is the main repository of reserve substances in the seeds of this species, as well as the main storage proteins, in order to provide basic knowledge that helps to better target the use of the acai seed.