title: A single amino acid mutation ofOsSBEIIbcontributes to resistant starch accumulation in rice.
abstract: Foods rich in resistant starch can help prevent various diseases, including diabetes, colon cancers, diarrhea, and chronic renal and hepatic diseases. Variations in starch biosynthesis enzymes could contribute to the high content of resistant starch in some cultivars of rice (Oryza sativaL.). Our previously published work indicated that thesbe3-rsgene in the rice mutant line, 'Jiangtangdao1' was a putative allele of the rice starch branching enzyme geneSBEIIb(previously known asSBE3);sbe3-rsmight control the biosynthesis of the high resistant starch content in the rice line. Biomolecular analysis showed that the activity of SBEs was significantly lower in soluble extracts of immature seeds harvested from 'Jiangtangdao1' 15 days after flowering than in the extracts of the wild-type rice line 'Huaqingdao'. We performed gene complementation assays by introducing the wild-typeOsSBEIIbinto thesbe3-rsmutant 'Jiangtangdao1'. The genetically complemented lines demonstrated restored seed-related traits. The structures of endosperm amylopectin and the morphological and physicochemical properties of the starch granules in the transformants recovered to wild-type levels. This study provides evidence thatsbe3-rsis a novel allele ofOsSBEIIb, responsible for biosynthesis of high resistant starch in 'Jiangtangdao1'.
authors: Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences , 1000 Jingqi Road, Fengxian District, Shanghai 201403 , China.
authors: Ruifang
authors: R
authors: Yang
authors: Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences , 1000 Jingqi Road, Fengxian District, Shanghai 201403 , China.
authors: Jianjiang
authors: J
authors: Bai
authors: Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences , 1000 Jingqi Road, Fengxian District, Shanghai 201403 , China.
authors: Jun
authors: J
authors: Fang
authors: Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences , 1000 Jingqi Road, Fengxian District, Shanghai 201403 , China.
authors: Ying
authors: Y
authors: Wang
authors: National Academy of Agricultural Science (South Korea) , Suwon City , Korea 441-857.
authors: Gangseob
authors: G
authors: Lee
authors: Crop Breeding and Cultivation Research Institute, Shanghai Academy of Agricultural Sciences , 1000 Jingqi Road, Fengxian District, Shanghai 201403 , China.
authors: Zhongze
authors: Z
authors: Piao
keywords: Jiangtangdao1; complementation assay; resistant starch; rice; sbe3-rs; starch branching enzyme