[Show abstract][Hide abstract]ABSTRACT: The Streptomyces phage phiC31 integrase was tested for its ability to excise transgenic DNA from the wheat genome by site-specific recombination. Plants that stably express phiC31 integrase were crossed to plants carrying a target construct bearing the phiC31 recognition sites, attP and attB. In the progeny, phiC31 recombinase mediates recombination between the att sites of the target locus, which results in excision of the intervening DNA. Recombination events could be identified in 34 independent wheat lines by PCR and Southern blot analysis and by sequencing of the excision footprints. Recombinant loci were inherited to the subsequent generation. The results presented here establish the integrase-att system as a tool for catalysing the precise elimination of DNA sequences from wheat chromosomes.
[Show abstract][Hide abstract]ABSTRACT: The Triticeae cereals comprise wheat, barley, rye and triticale. Together, these crops provide a major proportion of the food
and feed produced and consumed worldwide. Biotechnological approaches to the improvement of Triticeae cereals may thus largely
contribute to cope with the challenging future demands on agricultural production. This chapter provides comprehensive information
on technologies for the generation and characterization of stably transgenic Triticeae plants and on available systems of
transgene expression and targeted knock-down of endogenous genes. Further, transgenic approaches to the improvement of Triticeae
crops are reviewed with particular emphasis on: (i) tolerance to abiotic stress such as drought, salinity and heavy metal
toxicity, (ii) resistance to viral and fungal pathogens and pathogenic insects and (iii) grain quality features and the development
of transgenic lines to produce valuable molecules for industrial and pharmaceutical use.