A Heavy Metal-Associated Protein (AcHMA1) from the Halophyte, Atriplex canescens (Pursh) Nutt., Confers Tolerance to Iron and Other Abiotic Stresses When Expressed in Saccharomyces cerevisiae

International Journal of Molecular Sciences

Xin-Hua Sun¹  Gang Yu¹  Jing-Tao Li²  Pan Jia²  Ji-Chao Zhang²  Cheng-Guo Jia²  Yan-Hua Zhang¹ 

[1] Plant Science, Jilin University, Changchun130062, Jilin, China;

关键词: HMA (heavy metal-associated) domain;    Atriplex canescens;    Fe tolerance;    abiotic stress;    yeast expression;   

DOI  :  10.3390/ijms150814891

来源: mdpi

【 摘 要 】

Many heavy metals are essential for metabolic processes, but are toxic at elevated levels. Metal tolerance proteins provide resistance to this toxicity. In this study, we identified and characterized a heavy metal-associated protein, AcHMA1, from the halophyte, Atriplex canescens. Sequence analysis has revealed that AcHMA1 contains two heavy metal binding domains. Treatments with metals (Fe, Cu, Ni, Cd or Pb), PEG6000 and NaHCO₃ highly induced AcHMA1 expression in A. canescens, whereas NaCl and low temperature decreased its expression. The role of AcHMA1 in metal stress tolerance was examined using a yeast expression system. Expression of the AcHMA1 gene significantly increased the ability of yeast cells to adapt to and recover from exposure to excess iron. AcHMA1 expression also provided salt, alkaline, osmotic and oxidant stress tolerance in yeast cells. Finally, subcellular localization of an AcHMA1/GFP fusion protein expressed in tobacco cells showed that AcHMA1 was localized in the plasma membrane. Thus, our results suggest that AcHMA1 encodes a membrane-localized metal tolerance protein that mediates the detoxification of iron in eukaryotes. Furthermore, AcHMA1 also participates in the response to abiotic stress.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.