title: Molecular cloning and expression analysis of the sucrose transporter gene family from Theobroma cacao L.
abstract: In this study, we performed cloning and expression analysis of six putative sucrose transporter genes, designated TcSUT1, TcSUT2, TcSUT3, TcSUT4, TcSUT5 and TcSUT6, from the cacao genotype 'TAS-R8'. The combination of cDNA and genomic DNA sequences revealed that the cacao SUT genes contained exon numbers ranging from 1 to 14. The average molecular mass of all six deduced proteins was approximately 56 kDa (range 52 to 66 kDa). All six proteins were predicted to exhibit typical features of sucrose transporters with 12 trans-membrane spanning domains. Phylogenetic analysis revealed that TcSUT2 and TcSUT4 belonged to Group 2 SUT and Group 4 SUT, respectively, and the other TcSUT proteins were belonging to Group 1 SUT. Real-time PCR was conducted to investigate the expression pattern of each member of the SUT family in cacao. Our experiment showed that TcSUT1 was expressed dominantly in pods and that, TcSUT3 and TcSUT4 were highly expressed in both pods and in bark with phloem. Within pods, TcSUT1 and TcSUT4 were expressed more in the seed coat and seed from the pod enlargement stage to the ripening stage. TcSUT5 expression sharply increased to its highest expression level in the seed coat during the ripening stage. Expression pattern analysis indicated that TcSUT genes may be associated with photoassimilate transport into developing seeds and may, therefore, have an impact on seed production.
authors.affiliation: Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wanning 571533, PR China; Key Laboratory of Genetic Resources Utilization of Spice and Beverage Crops, Ministry of Agriculture, Wanning 571533, PR China; Hainan Provincial Key Laboratory of Genetic Improvement and Quality Regulation for Tropical Spice and Beverage Crops, Wanning 571533, PR China.
authors.forename: Fupeng
authors.initials: F
authors.lastname: Li
authors.affiliation: Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wanning 571533, PR China; Key Laboratory of Genetic Resources Utilization of Spice and Beverage Crops, Ministry of Agriculture, Wanning 571533, PR China; Hainan Provincial Key Laboratory of Genetic Improvement and Quality Regulation for Tropical Spice and Beverage Crops, Wanning 571533, PR China.
authors.forename: Baoduo
authors.initials: B
authors.lastname: Wu
authors.affiliation: Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wanning 571533, PR China; Key Laboratory of Genetic Resources Utilization of Spice and Beverage Crops, Ministry of Agriculture, Wanning 571533, PR China; Hainan Provincial Key Laboratory of Genetic Improvement and Quality Regulation for Tropical Spice and Beverage Crops, Wanning 571533, PR China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Qin
authors.affiliation: Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wanning 571533, PR China; Key Laboratory of Genetic Resources Utilization of Spice and Beverage Crops, Ministry of Agriculture, Wanning 571533, PR China; Hainan Provincial Key Laboratory of Genetic Improvement and Quality Regulation for Tropical Spice and Beverage Crops, Wanning 571533, PR China.
authors.forename: Lin
authors.initials: L
authors.lastname: Yan
authors.affiliation: Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wanning 571533, PR China; Key Laboratory of Genetic Resources Utilization of Spice and Beverage Crops, Ministry of Agriculture, Wanning 571533, PR China; Hainan Provincial Key Laboratory of Genetic Improvement and Quality Regulation for Tropical Spice and Beverage Crops, Wanning 571533, PR China.
authors.forename: Chaoyun
authors.initials: C
authors.lastname: Hao
authors.affiliation: Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wanning 571533, PR China; Key Laboratory of Genetic Resources Utilization of Spice and Beverage Crops, Ministry of Agriculture, Wanning 571533, PR China; Hainan Provincial Key Laboratory of Genetic Improvement and Quality Regulation for Tropical Spice and Beverage Crops, Wanning 571533, PR China.
authors.forename: Lehe
authors.initials: L
authors.lastname: Tan
authors.affiliation: Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wanning 571533, PR China; Key Laboratory of Genetic Resources Utilization of Spice and Beverage Crops, Ministry of Agriculture, Wanning 571533, PR China; Hainan Provincial Key Laboratory of Genetic Improvement and Quality Regulation for Tropical Spice and Beverage Crops, Wanning 571533, PR China. Electronic address: labcacao@gmail.com.
authors.forename: Jianxiong
authors.initials: J
authors.lastname: Lai
mesh_terms: D002099:Cacao / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D026901:Membrane Transport Proteins / Q000096:biosynthesis / Q000235:genetics; D008970:Molecular Weight; D024301:Plant Bark / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics; D018547:Plant Stems / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000235:genetics / Q000378:metabolism
chemical_list: D026901:Membrane Transport Proteins; D010940:Plant Proteins; C078729:sucrose transport protein, plant
keywords: Cloning; Expression pattern; Sucrose transporter; Theobroma cacao