Overexpression of sucrose transporter gene PbSUT2 from Pyrus bretschneideri, enhances sucrose content in Solanum lycopersicum fruit

• Published in: Plant physiology and biochemistry Vol. 105; pp. 150 - 161
• Main Authors: Wang, Li-Fen, Qi, Xiao-Xiao, Huang, Xiao-San, Xu, Lin-Lin, Jin, Cong, Wu, Jun, Zhang, Shao-Ling
• Format: Journal Article
• Language: English
• Published: France Elsevier Masson SAS 01.08.2016
• Subjects: Amino Acid Sequence; amino acids; Arabidopsis; Cell Membrane - metabolism; Cloning, Molecular; DNA, Complementary - genetics; Flowering; Flowers - physiology; fructose; Fruit - genetics; Fruit - metabolism; fruits; Gene Expression Regulation, Plant; gene overexpression; genes; Genes, Plant; glucose; leaves; Lycopersicon esculentum - anatomy & histology; Lycopersicon esculentum - genetics; Lycopersicon esculentum - metabolism; Membrane Transport Proteins - chemistry; Membrane Transport Proteins - genetics; Membrane Transport Proteins - metabolism; onions; Pear; pears; Phenotype; Photosynthesis; Photosynthetic rate; Phylogeny; plant growth; Plant Leaves - physiology; Plant Proteins - chemistry; Plant Proteins - genetics; Plant Proteins - metabolism; Plants, Genetically Modified; plasma membrane; protoplasts; Pyrus - genetics; Pyrus bretschneideri; Real-Time Polymerase Chain Reaction; Sequence Alignment; Sequence Analysis, DNA; Solanum lycopersicum; Subcellular Fractions - metabolism; sucrose; Sucrose - metabolism; Sucrose transporter; Sugar content; tomatoes; transgenic plants; Transgenic tomato; transporters; Flowering; Photosynthetic rate; Sucrose transporter; Pear; Sugar content; Transgenic tomato
• ISSN: 0981-9428; 1873-2690; 1873-2690
• DOI: 10.1016/j.plaphy.2016.04.019

Sucrose transporters (SUTs) belong to the major facilitator superfamily. The function of SUTs has been intensively investigated in some higher plants, whereas that in pear fruit is unknown. In this study, the cloning and functional characterization of a sucrose transporter, PbSUT2, in pear (Pyrus bretschneideri Rehd. cv. ‘Yali’) fruits are reported. PbSUT2 encoded a protein of 498 amino acid residues, and was localized in the plasma membrane of transformed onion epidermal cells and Arabidopsis protoplasts. Phylogenetic analysis revealed that PbSUT2 belonged to the SUT4 clade. The phenotype of overexpression of PbSUT2 tomato plants included early flowering, higher fruit quantity and lower plant height. Overexpression of PbSUT2 in transgenic tomato plants led to increases in the net photosynthetic rate in leaves and sucrose content in mature fruit compared with wild-type tomato plants, and a decrease in the contents of glucose, fructose and total soluble sugars in mature fruits. These results suggested that PbSUT2 affected sucrose content in sinks and the flowering phase during tomato plant growth and development. [Display omitted] •A new sucrose transporter gene PbSUT2 was cloned from pear fruit.•PbSUT2 was localized in the plasma membrane and belonged to SUT4 clade.•Overexpression of PbSUT2 led to increase sucrose content of tomato fruit.•PbSUT2 affected the photosynthetic rate and phenotype of transgenic tomato plant.