title: Gene structure, phylogeny and expression profile of the sucrose synthase gene family in cacao (Theobroma cacao L.).
abstract: In higher plants, sucrose synthase (Sus, EC 2.4.1.13) is widely considered as a key enzyme involved in sucrose metabolism. Although, several paralogous genes encoding different isozymes of Sus have been identified and characterized in multiple plant genomes, to date detailed information about the Sus genes is lacking for cacao. This study reports the identification of six novel Sus genes from economically important cacao tree. Analyses of the gene structure and phylogeny of the Sus genes demonstrated evolutionary conservation in the Sus family across cacao and other plant species. The expression of cacao Sus genes was investigated via real-time PCR in various tissues, different developmental phases of leaf, flower bud and pod. The Sus genes exhibited distinct but partially redundant expression profiles in cacao, with TcSus1, TcSus5 and TcSus6, being the predominant genes in the bark with phloem, TcSus2 predominantly expressing in the seed during the stereotype stage. TcSus3 and TcSus4 were significantly detected more in the pod husk and seed coat along the pod development, and showed development dependent expression profiles in the cacao pod. These results provide new insights into the evolution, and basic information that will assist in elucidating the functions of cacao Sus gene family.
authors.affiliation: Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Genetic Resources Utilization of Spice and Beverage Crops, Ministry of Agriculture, Wanning 571533, People's Republic of China.labcacao@gmail.com.
authors.forename: Fupeng
authors.initials: F
authors.lastname: Li
authors.forename: Chaoyun
authors.initials: C
authors.lastname: Hao
authors.forename: Lin
authors.initials: L
authors.lastname: Yan
authors.forename: Baoduo
authors.initials: B
authors.lastname: Wu
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Qin
authors.forename: Jianxiong
authors.initials: J
authors.lastname: Lai
authors.forename: Yinghui
authors.initials: Y
authors.lastname: Song
mesh_terms: D000595:Amino Acid Sequence; D002099:Cacao / Q000201:enzymology* / Q000235:genetics*; D005091:Exons / Q000235:genetics; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005964:Glucosyltransferases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D007438:Introns / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D011401:Promoter Regions, Genetic / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D005964:Glucosyltransferases; C022699:sucrose synthase