Constitutive expression of cell wall invertase genes increases grain yield and starch content in maize.
Grain size, number and starch content are important determinants of grain yield and quality. One of the most important biological processes that determine these components is the carbon partitioning during the early grain filling, which requires the function of cell wall invertase. Here, we showed the constitutive expression of cell wall invertase-encoding gene from Arabidopsis, rice (Oryza sativa) or maize (Zea mays), driven by the cauliflower mosaic virus (CaMV) 35S promoter, all increased cell wall invertase activities in different tissues and organs, including leaves and developing seeds, and substantially improved grain yield up to 145.3% in transgenic maize plants as compared to the wild-type plants, an effect that was reproduced in our 2-year field trials at different locations. The dramatically increased grain yield is due to the enlarged ears with both enhanced grain size and grain number. Constitutive expression of the invertase-encoding gene also increased total starch content up to 20% in the transgenic kernels. Our results suggest that cell wall invertase gene can be genetically engineered to improve both grain yield and grain quality in crop plants.
National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China.
Bei
B
Li
Hua
H
Liu
Yue
Y
Zhang
Tao
T
Kang
Li
L
Zhang
Jianhua
J
Tong
Langtao
L
Xiao
Hongxia
H
Zhang
D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics; D018533:Biomass; D002241:Carbohydrates / Q000032:analysis; D002473:Cell Wall / Q000201:enzymology*; D018556:Crops, Agricultural; D002523:Edible Grain / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D005816:Genetic Complementation Test; D009154:Mutation; D012275:Oryza / Q000201:enzymology / Q000235:genetics; D010788:Photosynthesis; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018520:Plant Shoots / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D030821:Plants, Genetically Modified; D013213:Starch / Q000032:analysis / Q000378:metabolism*; D019076:Transgenes; D003313:Zea mays / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D043324:beta-Fructofuranosidase / Q000235:genetics* / Q000378:metabolism
D002241:Carbohydrates; D010940:Plant Proteins; D013213:Starch; D043324:beta-Fructofuranosidase
GIF1; cell wall invertase; grain yield; maize; starch content; transgenic plants