Characterization of wheat lacking B-type starch granules.

The physicochemical and agronomic properties of a new form of bread wheat lacking B-type starch granules (BlessT) were assessed. Three BlessT mutant lines made by combining homoeologous deletions of a gene responsible for the control of B-granule content, were compared with two sibling lines with normal starch phenotype and the parent line, cv. Paragon.

Strategies to improve wheat for human health.

Despite their economic importance and growing demand, concerns are emerging around wheat-based foods and human health. Most wheat-based foods are made from refined white flour rather than wholemeal flour, and the overconsumption of these products may contribute to the increasing global prevalence of chronic diseases, particularly type 2 diabetes and obesity. Here, we review how the amount, composition and interactions of starch and cell wall polysaccharides, the major carbohydrate components in refined wheat products, impact human health.

encodes a prolamin-box-binding transcription factor that controls embryo growth in barley and wheat.

Mutations at the locus in barley have multiple effects on grain development, including an increase in embryo size and a decrease in endosperm starch content. The gene underlying was identified by genetic mapping and mutations in this gene were identified in all four barley alleles. encodes a transcription factor called Prolamin Binding Factor (PBF).

: A Locus Responsible for Controlling -Mediated Transformability in Barley.

In barley ( L.), -mediated transformation efficiency is highly dependent on genotype with very few cultivars being amenable to transformation. Golden Promise is the cultivar most widely used for barley transformation and developing embryos are the most common donor tissue.

A carbohydrate-binding protein, B-GRANULE CONTENT 1, influences starch granule size distribution in a dose-dependent manner in polyploid wheat.

In Triticeae endosperm (e.g. wheat and barley), starch granules have a bimodal size distribution (with A- and B-type granules) whereas in other grasses the endosperm contains starch granules with a unimodal size distribution.

Barley mutants are unique amongst shrunken-endosperm mutants in having abnormally large embryos.

Many shrunken endosperm mutants of barley ( L.) have been described and several of these are known to have lesions in starch biosynthesis genes. Here we confirm that one type of shrunken endosperm mutant, (so called because it was first identified as a high-lysine mutant) has an additional phenotype: as well as shrunken endosperm it also has enlarged embryos.

Transfer of a starch phenotype from wild wheat to bread wheat by deletion of a locus controlling B-type starch granule content.

Our previous genetic analysis of a tetraploid wild wheat species, Aegilops peregrina, predicted that a single gene per haploid genome, Bgc-1, controls B-type starch granule content in the grain. To test whether bread wheat (Triticum aestivum L.) has orthologous Bgc-1 loci, we screened a population of γ-irradiated bread wheat cv.

Use of advanced recombinant lines to study the impact and potential of mutations affecting starch synthesis in barley.

The effects on barley starch and grain properties of four starch synthesis mutations were studied during the introgression of the mutations from diverse backgrounds into an elite variety. The (ADPglucose transporter), (granule-bound starch synthase), (debranching enzyme isoamylase 1) and (starch synthase IIa) mutations were introgressed into NFC Tipple to give mutant and wild-type BCF families with different genomic contributions of the donor parent. Comparison of starch and grain properties between the donor parents, the BCF families and NFC Tipple allowed the effects of the mutations to be distinguished from genetic background effects.

Grain development in Brachypodium and other grasses: possible interactions between cell expansion, starch deposition, and cell-wall synthesis.

To explain the low levels of starch, high levels of (1,3;1,4)-β-glucan, and thick cell walls in grains of Brachypodium distachyon L. relative to those in other Pooideae, aspects of grain development were compared between B. distachyon and barley (Hordeum vulgare L.

A rice mutant lacking a large subunit of ADP-glucose pyrophosphorylase has drastically reduced starch content in the culm but normal plant morphology and yield.

A mutant of rice (Oryza sativa L.) was identified with a Tos17 insertion in Os05g50380, a gene encoding a plastidial large subunit (LSU) of ADP-glucose pyrophosphorylase (AGPase) that was previously called OsAPL3 or OsAGPL1. The insertion prevents the production of a normal transcript.

Waxy phenotype evolution in the allotetraploid cereal broomcorn millet: mutations at the GBSSI locus in their functional and phylogenetic context.

Waxy mutants, in which endosperm starch contains ~100% amylopectin rather than the wild-type composition of ~70% amylopectin and ~30% amylose, occur in many domesticated cereals. The cultivation of waxy varieties is concentrated in east Asia, where there is a culinary preference for glutinous-textured foods that may have developed from ancient food processing traditions. The waxy phenotype results from mutations in the GBSSI gene, which catalyzes amylose synthesis.

Subcellular analysis of starch metabolism in developing barley seeds using a non-aqueous fractionation method.

Compartmentation of metabolism in developing seeds is poorly understood due to the lack of data on metabolite distributions at the subcellular level. In this report, a non-aqueous fractionation method is described that allows subcellular concentrations of metabolites in developing barley endosperm to be calculated. (i) Analysis of subcellular volumes in developing endosperm using micrographs shows that plastids and cytosol occupy 50.

Identification of a major QTL controlling the content of B-type starch granules in Aegilops.

Starch within the endosperm of most species of the Triticeae has a unique bimodal granule morphology comprising large lenticular A-type granules and smaller near-spherical B-type granules. However, a few wild wheat species (Aegilops) are known to lack B-granules. Ae.