Identification and expression analysis of a catalase gene docat1 in dendrobium officinale / 中国药学杂志

ABSTRACT

OBJECTIVE: To isolate and characterize a catalase gene DoCAT1, the full length cDNA was cloned, in a rare endangered medicinal orchid species Dendrobium officinale, followed by bioinformatics analysis and expression pattern detection. METHODS: RACE Technology was used for gene clone. Characteristics of physiochemical properties, conserved domains and subcellular localization of the protein were determined using a series of bioinformatics tools. The analyses of multiple alignment and phylogenetic tree were performed using DNASTAR 6.0 and MEGA 6.0 softwares, respectively. Real time quantitative PCR was used for gene expression analysis. RESULTS: The full length cDNA of DoCAT1 was 1 796 bp in length, encoding a 492 amino acid protein with a molecular weight of 56.90×103 and an isoelectric point of 6.7. The deduced DoCAT1 protein, without transmembrane or signal peptide residues, contains catalase core domain (18-401), active site (54-70), heme binding site (344-352) and multiple conserved motifs. DoCAT1 had high identities (83.3%-88.3%) with CATs proteins from various plants; DoCAT1 belonged to class III of the CATs evolutionary tree. DoCAT1 gene was differentially and organs specifically expressed. The transcripts were more abundant in the roots, with 4.27 fold, then in the leaves and the lowest in the stems. CONCLUSION: Molecular characterization of DoCAT1 provides important basis for the growth and development and stress adaptation in D. officinale.