Combining mutations at genes encoding key enzymes involved in starch synthesis affects the amylose content, carbohydrate allocation and hardness in the wheat grain. Issue 10 (17th April 2018)

• Record Type: Journal Article
• Authors: Botticella, Ermelinda; Sestili, Francesco; Sparla, Francesca; Moscatello, Stefano; Marri, Lucia; Cuesta‐Seijo, Jose A.; Falini, Giuseppe; Battistelli, Alberto; Trost, Paolo; Lafiandra, Domenico
• Is Part Of: Plant biotechnology journal. Volume 16:Issue 10(2018)
• Page Start: 1723
• Page End: 1734
• Publication Date: 2018-04-17
• Subjects: amylose -- carbohydrates allocation -- cell wall polysaccharides -- gene expression -- kernel hardness -- resistant starch; Plant biotechnology -- Periodicals; Plant genetic engineering -- Periodicals; 630.272
• DOI: 10.1111/pbi.12908
• Languages: English
• ISSNs: 1467-7644

Abstract

Summary: Modifications to the composition of starch, the major component of wheat flour, can have a profound effect on the nutritional and technological characteristics of the flour's end products. The starch synthesized in the grain of conventional wheats ( Triticum aestivum ) is a 3:1 mixture of the two polysaccharides amylopectin and amylose. Altering the activity of certain key starch synthesis enzymes (GBSSI, SSIIa and SBEIIa) has succeeded in generating starches containing a different polysaccharide ratio. Here, mutagenesis, followed by a conventional marker‐assisted breeding exercise, has been used to generate three mutant lines that produce starch with an amylose contents of 0%, 46% and 79%. The direct and pleiotropic effects of the multiple mutation lines were identified at both the biochemical and molecular levels. Both the structure and composition of the starch were materially altered, changes which affected the functionality of the starch. An analysis of sugar and nonstarch polysaccharide content in the endosperm suggested an impact of the mutations on the carbon allocation process, suggesting the existence of cross‐talk between the starch and carbohydrate synthesis pathways.