Dimerization and protease resistance : new insight into the function of PR-1
Copyright © 2012 Elsevier GmbH. All rights reserved.
| Veröffentlicht in: | Journal of plant physiology. - 1979. - 170(2013), 1 vom: 01. Jan., Seite 105-10 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2013
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| Zugriff auf das übergeordnete Werk: | Journal of plant physiology |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Plant Proteins Recombinant Proteins pathogenesis-related proteins, plant Peptide Hydrolases EC 3.4.- |
| Zusammenfassung: | Copyright © 2012 Elsevier GmbH. All rights reserved. The group 1 pathogenesis-related (PR-1) proteins have long been considered hallmarks of hypersensitive response/defense pathways in plants, but their biochemical functions are still obscure despite resolution of the NMR/X-ray structures of several PR-1-like proteins, including P14a (the prototype PR-1). We report here the characterization of two basic PR-1 proteins (PR-1-1 and PR-1-5) recently identified from hexaploid wheat (Triticum aestivum). Both proteins were expressed in Pichia pastoris as a single major species of ∼15 kDa. Sequence identity of the expressed PR-1 proteins was verified by MALDI-TOF/TOF analysis. Accumulation of the native PR-1-5 protein in pathogen-challenged wheat was confirmed by protein gel blot analysis. Low-temperature SDS-PAGE and yeast two-hybrid assays revealed that PR-1-1 exists primarily as a monomer whereas PR-1-5 forms homodimers. Both PR-1 proteins are resistant to proteases compared to bovine serum albumin, but PR-1-1 shows resistance mainly to subtilisin and protease K (serine proteases) whereas PR-1-5 shows resistance to subtilisin, protease K and papain (a cysteine protease). Site-specific mutations at the five putative active sites in the PR-1 domain all affected dimerization, with the mutations at Glu-72 and Glu-102 (in the PR-1-5 numeration) also diminishing protease resistance. Sequence analysis revealed that the Glu-72 and Glu-102 residues are located in motif-like sequences that are conserved in both PR-1 and the human apoptosis-related caspase proteins. These findings prompt us to examine the function of PR-1 for a role in protease-mediated programmed cell death pathways in plants |
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| Beschreibung: | Date Completed 10.05.2013 Date Revised 30.09.2020 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1618-1328 |
| DOI: | 10.1016/j.jplph.2012.08.006 |