Grain subproteome responses to nitrogen and sulfur supply in diploid wheat Triticum monococcum ssp. monococcum

Abstract

Wheat grain storage proteins (GSPs) make up most of the protein content of grain and determine flour end-use value. The synthesis and accumulation of GSPs depend highly on nitrogen (N) and sulfur (S) availability and it is important to understand the underlying control mechanisms. Here we studied how the einkorn (Triticum monococcum ssp. monococcum) grain proteome responds to different amounts of N and S supply during grain development. GSP composition at grain maturity was clearly impacted by nutrition treatments, due to early changes in the rate of GSP accumulation during grain filling. Large-scale analysis of the nuclear and albumin-globulin subproteomes during this key developmental phase revealed that the abundance of 203 proteins was significantly modified by the nutrition treatments. Our results showed that the grain proteome was highly affected by perturbation in the N:S balance. S supply strongly increased the rate of accumulation of S-rich α/β-gliadin and γ-gliadin, and the abundance of several other proteins involved in glutathione metabolism. Post-anthesis N supply resulted in the activation of amino acid metabolism at the expense of carbohydrate metabolism and the activation of transport processes including nucleocytoplasmic transit. Protein accumulation networks were analyzed. Several central actors in the response were identified whose variation in abundance was related to variation in the amounts of many other proteins and are thus potentially important for GSP accumulation. This detailed analysis of grain subproteomes provides information on how wheat GSP composition can possibly be controlled in low-level fertilization condition.

Variation in phosphorus and sulfur content shapes the genetic architecture and phenotypic associations within the wheat grain ionome

“…The strong phenotypic correlation between grain protein content and P is probably associated with the balance between the macroelements needed for the globoid crystal formations (Lott et al , ), where storage proteins may be associated with chelate complexes (Raboy et al , ). In the current study, we have obtained strong correlations between S and grain protein content, which can be explained by the strong coordination of N and S metabolisms in wheat that are affecting amino acid metabolism (Howarth et al , ) and grain proteome (Dai et al , ; Bonnot et al , ). Moreover, similar linkage was observed in barley when N deprivation affected also cysteine biosynthesis (Carfagna et al , ).…”

Is a Change of Protein Composition after Late Application of Nitrogen Sufficient to Improve the Baking Quality of Winter Wheat?

“…It was suggested [34] with an increase in nitrogen supply over unchanged sulfur supply, more N is available for biosynthesis, which causes a higher increase in glutenin with respect to gliadin. Simultaneously, the bread volume and gliadin to glutenin ratio has a negative correlation [35].…”

The bZIP transcription factor SPA Heterodimerizing Protein represses glutenin synthesis in Triticum aestivum

“…The LMW‐GS, α/β‐gliadin and γ‐gliadin, are classified as sulfur‐rich, and the HMW‐GS, ω1,2‐gliadin and ω5‐gliadin, as sulfur‐poor (Shewry et al ., , ). Sulfur deficiency decreases the concentration of sulfur‐rich proteins but increases the concentration of sulfur‐poor proteins, with the effect of maintaining a steady total level of GSPs (Zörb et al ., ; Dai et al ., ; Bonnot et al ., ).…”