Transgenic approach to improve wheat (Triticum aestivum L.) nutritional quality.

An amaranth (Amaranthus hypochondriacus) albumin gene, encoding the 35-kDa AmA1 protein of the seed, with a high content of essential amino acids, was used in the biolistic transformation of bread wheat (Triticum aestivum L.) variety Cadenza. The transformation cassette carried the ama1 gene under the control of a powerful wheat endosperm-specific promoter (1Bx17 HMW-GS). Southern-blot analysis of T(1) lines confirmed the integration of the foreign gene, while RT-PCR and Western-blot analyses of the samples confirmed the transcription and translation of the transgene. The effects of the extra albumin protein on the properties of flour, produced from bulked T(2) seeds, were calculated using total protein and essential amino acid content analysis, polymeric/monomeric protein and HMW/LMW glutenin subunit ratio measurements. The results indicated that not only can essential amino acid content be increased, but some parameters associated with functional quality may also be improved because of the expression of the AmA1 protein.