title: Cloning and characterization of HbMT2a, a metallothionein gene from Hevea brasiliensis Muell. Arg differently responds to abiotic stress and heavy metals.
abstract: Metallothioneins (MTs) are of low molecular mass, cysteine-rich proteins. They play an important role in the detoxification of heavy metals and homeostasis of intracellular metal ions, and protecting against intracellular oxidative damages. In this study a full-length cDNA of type 2 plant metallothioneins, HbMT2a, was isolated from 25 mM Polyethyleneglycol (PEG) stressed leaves of Hevea brasiliensis by RACE. The HbMT2a was 372bp in length and had a 237bp open reading frame (ORF) encoding for a protein of 78 amino acid residues with molecular mass of 7.772 kDa. The expression of HbMT2a in the detached leaves of rubber tree clone RY7-33-97 was up-regulated by Me-JA, ABA, PEG, H2O2, Cu(2+) and Zn(2+), but down-regulated by water. The role of HbMT2a protein in protecting against metal toxicity was demonstrated in vitro. PET-28a-HbMT2-beared Escherichia coli. Differential expression of HbMT2a upon treatment with 10 °C was observed in the detached leaves of rubber tree clone 93-114 which is cold-resistant and Reken501 which is cold-sensitive. The expression patterns of HbMT2a in the two rubber tree clones may be ascribed to a change in the level of endogenous H2O2.
authors: Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan 571737, China.
authors: Yan
authors: Y
authors: Li
authors: Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan 571737, China.
authors: Yue Yi
authors: YY
authors: Chen
authors: Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan 571737, China.
authors: Shu Guang
authors: SG
authors: Yang
authors: Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan 571737, China. Electronic address: wmtian9110@126.com.
authors: Wei Min
authors: WM
authors: Tian
mesh_terms: D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003001:Cloning, Molecular; D004361:Drug Tolerance; D004926:Escherichia coli / Q000187:drug effects* / Q000502:physiology*; D028482:Hevea / Q000145:classification* / Q000235:genetics / Q000378:metabolism*; D008668:Metallothionein / Q000235:genetics / Q000378:metabolism*; D019216:Metals, Heavy / Q000494:pharmacology*; D011994:Recombinant Proteins / Q000378:metabolism; D013045:Species Specificity; D013312:Stress, Physiological / Q000187:drug effects / Q000502:physiology*
chemical_list: D019216:Metals, Heavy; D011994:Recombinant Proteins; D008668:Metallothionein
keywords: Cold stress; Heavy metal iron; Metallothionein; Rubber tree