title: Cloning, heterologous expression and characterization of ascorbate peroxidase (APX) gene in laticifer cells of rubber tree (Hevea brasiliensis Muell. Arg.).
abstract: Ascorbate peroxidases (APXs) are a kind of crucial enzymes for removing reactive oxygen species (ROS) in plant cell. In the present study, a full-length cDNA encoding an APX, designated HbAPX, was isolated from Hevea brasiliensis by the rapid amplification of cDNA ends (RACE) method. HbAPX was 1174-bp in length and contained a 912-bp open reading frame (ORF) encoding a putative protein of 304 amino acids. The predicted molecular mass of HbAPX was 27.6 kDa (kDa) with an isoelectric point (pI) of 6.73. The phylogenetic analysis showed that HbAPX belonged to the cytosolic subgroup and was more relative to PtAPX and MdAPX2. By using PlantCare online analysis, such cis-acting elements as W-box and MRE were detected in the promoter region of HbAPX. Overproduction of recombinant HbAPX protein either in Escherichia coli or yeast enhanced their tolerance to such abiotic stresses as Cu(2+), Zn(2+), Na(2+) and hydrogen peroxide (H2O2). Ethrel application significantly down-regulated the expression of HbAPX and inhibited the activity of HbAPX in vivo. The ethrel-caused down-regulation of HbAPX may disturb the redox homeostasis in laticifer cells of rubber tree.
authors.affiliation: Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree/State Key Laboratory Breeding Base of Cultivation and Physiology for Tropical Crops, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou Hainan 571737, PR China. Electronic address: tianwang208@163.com.
authors.forename: Jinquan
authors.initials: J
authors.lastname: Chao
authors.affiliation: Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree/State Key Laboratory Breeding Base of Cultivation and Physiology for Tropical Crops, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou Hainan 571737, PR China. Electronic address: zhangshixin_1@163.com.
authors.forename: Shixin
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree/State Key Laboratory Breeding Base of Cultivation and Physiology for Tropical Crops, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou Hainan 571737, PR China. Electronic address: m13648609802@163.com.
authors.forename: Yueyi
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree/State Key Laboratory Breeding Base of Cultivation and Physiology for Tropical Crops, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou Hainan 571737, PR China. Electronic address: wmtian@163.com.
authors.forename: Wei-Min
authors.initials: WM
authors.lastname: Tian
mesh_terms: D000595:Amino Acid Sequence; D060387:Ascorbate Peroxidases / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D003001:Cloning, Molecular; D015536:Down-Regulation / Q000187:drug effects; D004926:Escherichia coli / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D028482:Hevea / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D009943:Organophosphorus Compounds / Q000494:pharmacology; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D012408:Rubber / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism
chemical_list: D009943:Organophosphorus Compounds; D010940:Plant Proteins; D011994:Recombinant Proteins; D012408:Rubber; D060387:Ascorbate Peroxidases; C005073:ethephon
keywords: Ascorbate peroxidase; Ethrel; Hevea brasiliensis Muell. Arg.; Laticifer cells; Redox homeostasis