基因编辑技术获得非转基因低麸小麦

面粉中的麸质蛋白(面筋)会引起部分人群的过敏而发生腹泻(乳糜泻),同时高蛋白含量会导致普通人的肥胖。降低谷蛋白含量,培育低麸小麦,是解决特殊人群无麸质饮食需求的可行途径。如今,科学家利用基因编辑技术抑制小麦醇溶蛋白α-gliadins的表达,培育出了非转基因的低麸小麦。

研究人员选取醇溶蛋白中引起过敏的重要抗原表位33-mer区域作为靶标,设计了2个sgRNA进行CRISPR/Cas9编辑敲除。结果显示,编辑后的小麦谷蛋白含量明显降低,引发的免疫反应活性降低了85%。

该产品可以很好地迎合当今无麸质饮食潮流的需求。

Plant Biotechnol J. 2017 Sep 18.

Low-gluten, non-transgenic wheat engineered with CRISPR/Cas9.

Author

Sánchez-León S, Gil-Humanes J2, Ozuna CV, Giménez MJ, Sousa C, Voytas DF, Barro F1.

1: Departamento de Mejora Genética Vegetal, Instituto de Agricultura Sostenible (IAS-CSIC), Spain; 2: Department of Genetics, Cell Biology, and Development, Center for Genome Engineering, University of Minnesota, USA.

Abstract

Celiac disease is an autoimmune disorder triggered in genetically predisposed individuals by the ingestion of gluten proteins from wheat, barley, and rye. The -gliadin gene family of wheat contains four highly stimulatory peptides, of which the 33-mer is the main immunodominant peptide in celiac patients. We designed two sgRNAs to target a conserved region adjacent to the coding sequence for the 33-mer in the -gliadin genes. Twenty-one mutant lines were generated, all showing strong reduction in -gliadins. Up to 35 different genes were mutated in one of the lines of the 45 different genes identified in the wild type, while immunoreactivity was reduced by 85%. Transgene-free lines were identified, and no off-target mutations have been detected in any of the potential targets. The low-gluten, transgene-free wheat lines described here could be used to produce low gluten foodstuff and serve as source material to introgress this trait into elite wheat varieties.