Increasing the starch content and grain weight of common wheat by overexpression of the cytosolic AGPase large subunit gene.
ADP-glucose pyrophosphorylase (AGPase) catalyzes the first committed step of starch synthesis. AGPase is a heterotetramer composed of two large subunits and two small subunits, has cytosolic and plastidial isoforms, and is detected mainly in the cytosol of endosperm in cereal crops. To investigate the effects of AGPase cytosolic large subunit gene (LSU I) on starch biosynthesis in higher plant, in this study, a TaLSU I gene from wheat was overexpressed under the control of an endosperm-specific promoter in a wheat cultivar (Yumai 34). PCR, Southern blot, and real-time RT-PCR analyses indicated that the transgene was integrated into the genome of transgenic plants and was overexpressed in their progeny. The overexpression of the TaLSU I gene remarkably enhanced AGPase activity, endosperm starch weight, grain number per spike, and single grain weight. Therefore, we conclude that overexpression of the TaLSU I gene enhances the starch biosynthesis in endosperm of wheat grains, having potential applications in wheat breeding to develop a high-yield wheat cultivar with high starch weight and kernel weight.
The National Engineering Research Centre for Wheat, Henan Agricultural University, #63 Nongye Road, Zhengzhou, Henan Province 450002, China. Electronic address: zkangg@163.com.
Guozhang
G
Kang
Guoqin
G
Liu
Xiaoqi
X
Peng
Liting
L
Wei
Chenyang
C
Wang
YunJi
Y
Zhu
Ying
Y
Ma
Yumei
Y
Jiang
Tiancai
T
Guo
D003600:Cytosol / Q000201:enzymology / Q000378:metabolism; D056625:Endosperm / Q000201:enzymology* / Q000254:growth & development / Q000378:metabolism; D017343:Genes, Plant; D051599:Glucose-1-Phosphate Adenylyltransferase / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D021122:Protein Subunits / Q000235:genetics* / Q000378:metabolism; D013213:Starch / Q000096:biosynthesis / Q000235:genetics*; D014908:Triticum / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
D010940:Plant Proteins; D021122:Protein Subunits; D013213:Starch; D051599:Glucose-1-Phosphate Adenylyltransferase
AGPase; Cytosolic large subunit; Overexpression; Starch; Wheat (Triticum aextivum L.)