Proteomics characterization of the synthesis and accumulation of starch and amino acid driven by high-nitrogen fertilizer in common buckwheat.

The KEGG and GO enrichment analysis of proteomics revealed the molecular mechanism of starch synthesis and accumulation driven by nitrogen fertilizer in common buckwheat grain filling. [Display omitted] • High N level significant increased starches content of common buckwheat. • The number of upregulated DEPs induced by N increased with the filling progress. • N induced six PYGs, one SUS and two AMYs significant upregulation at 30d. • Linear relationship between key protein expression and starch content. • N promoted arginine and lysine biosynthetic proteins types at late filling stage. The accumulation of starches and amino acid content of common buckwheat is promoted by Nitrogen (N), but the molecular mechanism is not clear. N applications with 0 (control group) and 180 kg/ha were designed. High-N significantly improved grain fullness and increased the starch, amylopectin and amylose content. The number of upregulated differentially expressed proteins (DEPs) induced by N gradually increased with the filling progress. N resulted in 139, 341 and 472DEPs significant upregulation at 10d, 20d and 30d and they were mainly related to the 'Starch and sucrose metabolism', 'Protein processing in endoplasmic reticulum' and 'Ribosome' by kyoto encyclopedia of genes and genomes analysis. High-N induced one sucrose synthase, two alpha-amylases and six alpha-glucan phosphorylases significant upregulation at 30d and one alpha-amylases upregulation at 10d, and the expression levels of these proteins showed a significant linear relationship with starch and amylose contents. N promoted the arginine and lysine biosynthesis at the late filling stage. These results elucidated that the mechanism of N promoted common buckwheat starches and amino acid accumulation. The identified crucial proteins may improve buckwheat quality. [ABSTRACT FROM AUTHOR]