title: Molecular Cloning and Expression Analysis of a Catalase Gene (NnCAT) from Nelumbo nucifera.
abstract: Rapid amplification cDNA end (RACE) assay was established to achieve the complete cDNA sequence of a catalase gene (NnCAT) from Nelumbo nucifera. The obtained full-length cDNA was 1666 bp in size and contained a 1476-bp open reading frame. The 3D structural model of NnCAT was constructed by homology modeling. The putative NnCAT possessed all the main characteristic amino acid residues and motifs of catalase (CAT) protein family, and the phylogenetic analysis revealed that NnCAT grouped together with high plants. Moreover, recombinant NnCAT showed the CAT activity (758 U/mg) at room temperature, holding high activity during temperature range of 20-50 °C, then the optimal pH of recombinant protein was assessed from pH 4 to pH 11. Additionally, real-time PCR assay demonstrated that NnCAT mRNA was expressed in various tissues of N. nucifera, with the highest expression in young leaf and lowest level in the root, and mRNA level of NnCAT was significantly augmented in response to short-time mechanical wounding. Different expression pattern of NnCAT gene suggested that NnCAT probably played a defensive role in the initial stages of oxidative stress, regulating the level of reactive oxygen species (ROS) by extracellular stimuli such as short-time mechanical wounding.
authors: College of Biological Engineering, Henan University of Technology, Zhengzhou, Henan, 450051, China.
authors: Chen
authors: C
authors: Dong
authors: State Key Laboratory of Hybrid Rice, College of Life Science, Wuhan University, Wuhan, 430072, China.
authors: Xingfei
authors: X
authors: Zheng
authors: State Key Laboratory of Hybrid Rice, College of Life Science, Wuhan University, Wuhan, 430072, China.
authors: Ying
authors: Y
authors: Diao
authors: Lotus Center, Wuhan University, Wuhan, 430072, China.
authors: Youwei
authors: Y
authors: Wang
authors: Lotus Center, Wuhan University, Wuhan, 430072, China.
authors: Mingquan
authors: M
authors: Zhou
authors: State Key Laboratory of Hybrid Rice, College of Life Science, Wuhan University, Wuhan, 430072, China. huzhongli@whu.edu.cn.
authors: Zhongli
authors: Z
authors: Hu
mesh_terms: D002374:Catalase / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D003001:Cloning, Molecular; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D008958:Models, Molecular; D031653:Nelumbo / Q000201:enzymology / Q000235:genetics; D010940:Plant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D017434:Protein Structure, Tertiary
chemical_list: D010940:Plant Proteins; D002374:Catalase
keywords: Catalase; Nelumbo nucifera; Reactive oxygen species; Tissue expression; cDNA