The putative functions of salt stress-responsive DAPs were investigated using GO enrichment, KEGG pathway enrichment and COG analyses (Fig. The distribution of protein coverage showed that coverage with less than 10, 10 -30%, and 30 100% accounted for 57.6, 33.9 and 8.4% in leaf (Fig. In leaves and roots, 60 and 70 low molecular weight proteins (Mr 100 kDa) were identified, respectively (Fig. The peptide number distribution of proteins indicated that 90% of identified proteins contained less than 8 segments (Fig. Statistical analyses showed that most peptides having 8-15 amino acids. The length and number distribution of the peptides is shown in Fig. In roots, 13,248 unique peptides and 3935 proteins were identified, of which 2541 (64.6%) of the proteins had at least two unique peptides.

In leaves, 10,121 unique peptides and 3175 proteins were identified against the UniProt database, where 1966 of the proteins (61.6%) had at least two unique peptides. Ī total of 31,438 and 39,522 MS/MS counts were generated from leaves and roots, respectively. These elicit different plant responses and may affect interpretation of results. In particular, salt treatment can be gradual (salt stress) or immediate (shock). While these studies are useful, we note that plant proteome responses to salt stress depend on its intensity, duration and the organ examined. studied proteome changes in seedlings, but only in shoots and roots, and after a very long exposure (50 mm NaCl for 72 h). the changes were only induced by short-term salt stress (30 min and 1 h) and examined only proteome/phosphoproteome changes in M14 leaves. only analyzed changes of membrane proteins in sugar beet monosomic addition line M14.

Isobaric tags for relative and absolute quantitation (iTRAQ) is one of the most reliable labeling techniques for proteome quantification, and has been used previously to analyze salt stress-induced proteome changes in sugar beet. Proteome analysis provides a more direct insight into molecular phenotype than transcriptome analysis.

Salt toxicity in beet seedlings