Plant Physiology Preview
Published on March 10, 2006; 10.1104/pp.105.073841
Received November 5, 2005
Returned for revision November 28, 2005
Accepted February 16, 2006
Identification and Characterization of a Stress-Inducible And a Constitutive Small Heat Shock Protein Targeted to the Matrix of Plant Peroxisomes
Changle Ma , Martin Haslbeck , Lavanya Babujee , Olaf Jahn , and Sigrun Reumann *
Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, Georg-August-University Goettingen, Justus-von-Liebig-Weg 11, D-37077 Goettingen, Germany
Department of Chemistry, Technical University Munich, D-85747 Garching, Germany
Max-Planck-Institute of Experimental Medicine, Proteomics Group, Hermann-Rein-Str. 3, D-37075 Goettingen, Germany
* Corresponding author; email: sreuman{at}gwdg.de.
Small heat-shock proteins (sHsps) are widespread molecular chaperones for which a peroxisomal localization has not yet been reported. The Arabidopsis genome encodes two sHsps with putative peroxisomal targeting signals type 1 or 2 (PTS1 or PTS2). As demonstrated by double labeling experiments using full-length fusion proteins with enhanced yellow fluorescent protein (EYFP) and deletion constructs lacking the putative targeting domains, AtHsp15.7 (At5g37670) and AtAcd31.2 (At1g06460) are targeted to the peroxisome matrix by a functional PTS1 (SKL>) and a functional PTS2 (RLx5HF), respectively. The peroxisomal localization of AtAcd31.2 was further confirmed by isolation of leaf peroxisomes from Arabidopsis by two successive sucrose density gradients, protein separation by one- and two-dimensional gel electrophoresis, and mass spectrometric protein identification. When AtHsp15.7 and AtAcd31.2 were heterologously expressed in yeast and directed to the cytosol by deletion of the PTSs, both sHsps were able to complement the morphological phenotype of Saccharomyces cerevisiae mutants deficient in the cytosolic homologs ScHsp42 or ScHsp26. According to expression studies by RT-PCR AtAcd31.2 is constitutively expressed, whereas AtHsp15.7 is hardly expressed under normal conditions, but strongly induced by heat and oxidative stress, the latter of which was triggered by the catalase inhibitor 3-aminotriazole or the herbicide paraquat applied by watering of whole plants or infiltration of rosette leaves. Thus, plants are exceptional among eukaryotes in employing sHsps in the peroxisome matrix to prevent unspecific aggregation of partially denatured proteins under both physiological and stress conditions.
This article has been cited by other articles:
|
|
|
|
 
C. Ma and S. Reumann
Improved prediction of peroxisomal PTS1 proteins from genome sequences based on experimental subcellular targeting analyses as exemplified for protein kinases from Arabidopsis
J. Exp. Bot.,
October 1, 2008;
59(13):
3767 - 3779.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
Y. Arai, M. Hayashi, and M. Nishimura
Proteomic Analysis of Highly Purified Peroxisomes from Etiolated Soybean Cotyledons
Plant Cell Physiol.,
April 1, 2008;
49(4):
526 - 539.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. Hageman, M. J. Vos, M. A. W. H. van Waarde, and H. H. Kampinga
Comparison of Intra-organellar Chaperone Capacity for Dealing with Stress-induced Protein Unfolding
J. Biol. Chem.,
November 23, 2007;
282(47):
34334 - 34345.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Reumann, L. Babujee, C. Ma, S. Wienkoop, T. Siemsen, G. E. Antonicelli, N. Rasche, F. Luder, W. Weckwerth, and O. Jahn
Proteome Analysis of Arabidopsis Leaf Peroxisomes Reveals Novel Targeting Peptides, Metabolic Pathways, and Defense Mechanisms
PLANT CELL,
October 1, 2007;
19(10):
3170 - 3193.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
T. Orth, S. Reumann, X. Zhang, J. Fan, D. Wenzel, S. Quan, and J. Hu
The PEROXIN11 Protein Family Controls Peroxisome Proliferation in Arabidopsis
PLANT CELL,
January 1, 2007;
19(1):
333 - 350.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
