Isolation And Characterization Of MADS-box Genes From Taihangia Rupestris

Gene duplication and diversification can provide the raw material for the innovation of new morphologies. The MADS-box genes encoding a family of transcription factors have undergone extensive gene duplication events and subsequent functional divergence during the evolution. Therefore, study on the sequence structures, expression patterns in the regulatory region, functions in the coding region and interaction behaviors of MADS-box genes can provide the evidence for the fate of the duplicate genes. MADS-box genes control diverse developmental processes in flowering plants ranging from root to flower and fruit development. In this study, seven MADS-box genes were isolated from Taihangia rupestris, a core eudicot species belonging to the Rosaceae by RACE (Rapid Amplification of cDNA Ends). Sequence analyses revealed that they share a high degree of the predicted protein sequence identity with AG, SHP (SHP1/2), PI, AP1, FUL and SEP1 from Arabidopsis and PhTM6 from Petunia, respectively. Therefore, the seven genes are termed TrAG (Taihangia rupestris AG), TrSHP (Taihangia rupestris SHP), TrPI (Taihangia rupestris PI), TrAP1 (Taihangia rupestris AP1), TrFUL (Taihangia rupestris FUL), TrSEP1 (Taihangia rupestris SEP1) and TrTM6 (Taihangia rupestris PhTM6), respectively.Firstly, the paralogous genes, TrAG and TrSHP, were used for further study. Phylogenetic analyses revealed that they are clade members of the euAG and PLE lineages, respectively. Expression patterns, functions and biochemical interaction patterns of TrAG and TrSHP were analyzed using RNA in situ hybridization, constitutive expression in Arabidopsis and yeast two-hybrid assays, respectively. In situ hybridization analyses show that both TrAG and TrSHP are mainly expressed in...