Cloning And Expression Analysis Of Sucrose Transporter In Neolamarckia Cadamba

Neolamarckia cadamba belongs to the family of Rubiaceae, an important fast-growing economic tree species, which makes a difference to the edible, medicinal and industrial aspects. And sucrose provides large amounts of nutrients for root, reproductive structure, storage and heterotrophic cells, in order to make sure that sink organization could receive adequate sucrose for the growth and development. Sucrose transporter plays a key role in transporting and distributing of sucrose to the membrane in whole plant. Therefore, the research of the sucrose transporter gene of Neolamarckia cadamba, helps to get a further understanding of the sucrose transport mechanism, and to make full use of it.The full-length c DNA of the three sucrose transporter genes were cloned from Neolamarckia cadamba, named NcSUT2, NcSUT3 and NcSUT4. These three genes encoded 522, 623, 505 amino acids respectively; and bioinformatics analysis showed that, the three genes encoding proteins belonged to a hydrophobic protein and had a typical sucrose transporter 12 transmembrane domain.Transient expression of NcSUT2-GFP,NcSUT3-GFP and NcSUT4-GFP fusion protein in Arabidopsis thaliana and Neolamarckia cadamba protoplasts showed that NcSUT2,NcSUT3 were localized on the plasma membrane,while NcSUT4 on the plasma membrane and chloroplastid.Real-time quantitative PCR showed that NcSUT2, NcSUT3, NcSUT4 expressed in phloem, leaves,roots,and the bark,but the expressive quantity were significantly different and changed with during seasons.On the other hand, the expressive quantity werediverse between different ages as well.