biologia plantarum

Biologia plantarum 56:197-199, 2012 | DOI: 10.1007/s10535-012-0042-1

Overexpression of AtHsp90.3 in Arabidopsis thaliana impairs plant tolerance to heavy metal stress

H. M. Song^1,2, H. Z. Wang^1,*, X. B. Xu^1,*

¹ College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, P.R. China

² The Institute of Crop and Nuclear Technology Utilization, Zhejiang Academy of Agricultural Sciences, Hangzhou, P.R. China

The functions of cytosolic heat shock protein AtHsp90.3 in response to heavy metal stress were characterized by using expression of AtHsp90.3 gene in yeast and Arabidopsis thaliana. AtHsp90.3 supported the Saccharomyces cerevisiae Hsp90 knockout strain R0005 growth and maintaining cells membrane integrity under cadmium and arsenic stresses, which was compatible with the components of ScHsc82 machinery. However, constitutive overexpression of AtHsp90.3 in Arabidopsis impaired plant tolerance to Cd stress with lower germination rate and shorter root length, decreased contents of phytochelatins (PCs) and glutathione (GSH), inhibited activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), and increased content of malondialdehyde (MDA). These results suggested that proper homeostasis of Hsp90 was critical for cellular response and/or tolerance to heavy metal stress in plants.

Keywords: antioxidants; arsenic; cadmium; heat shock proteins; malondialdehyde; phytochelatins

Subjects: arsenic; cadmium; heat shock proteins; malondialdehyde; phytochelatins; gene expression; glutathione; superoxide dismutase; catalase; peroxidase

Received: February 26, 2010; Accepted: March 29, 2011; Published: March 1, 2012  Show citation