The aim of the study was to understand the molecular and biochemical mechanisms underpinning the effect of nitrogen (N) on barley (Hordeum vulgare) storage protein production (hordeins) during grain filling. Using a combination of advanced biochemistry methods, we could comprehensively describe changes in transcripts (using DNA microarray and qRT-PCR), amino acids (Ultra Performance Liquid Chromatography) and protein abundance (2D-DIGE combined with MS/MS). Examining all known hordein homologues revealed markedly different temporal profiles in their expression patterns. Furthermore, different N-regimes caused significant differences in both quantity and quality of the storage proteins transcripts. Principal Component Analysis of the amino acid (AA) profiles also indicated dissimilarity in individual AA percentages, correlated to hordein content. The abundance values of proteins of interest confirmed the various hordein patterns during grain development and the differential response to environmental stimuli.
Proceedings of 19th Eucarpia General Congress: Plant Breeding for Future Generations, 2012, p. 176-179