Rhizobium colonization induced changes in membrane-bound and soluble hydroxyproline-rich glycoprotein composition in pea.
Author
Summary, in English
Abundance and distribution of plant cell surface proteins of the hydroxyproline-rich glycoprotein (HRGP) class were studied in the pea-Rhizobium symbiosis using immunoblot analysis. The MAC 265-epitope was especially abundant in pea root nodules containing nitrogen-fixing Rhizobium bacteria. A 180-kDa MAC 265-HRGP dominated in pea shoot plasma membranes, while almost no MAC 265-HRGP was detected in root plasma membranes. We show here that a major difference between the plant-derived peribacteroid membrane of the symbiosomes and the root plasma membrane was the presence of a 100-kDa MAC 265-HRGP in the former. Arabinogalactan proteins (AGPs), as recognized by the monoclonal antibodies MAC 207 and JIM 8, were not detected in the peribacteroid membrane, while two isoforms (100 and 220 kDa) were detected in shoot and root plasma membranes. Specific MAC 265-HRGP isoforms were found in the peribacteroid space fraction of the symbiosomes and thus as soluble proteins in the interface between the symbionts. The abundance of the MAC 265-epitope was much reduced in non-nitrogen-fixing nodules when this phenotype resulted from a dicarboxylate transport mutation in Rhizobium. There was no reduction in the abundance of the MAC 265-epitope in non-fixing phenotypes resulting from a mutation in the plant. The results suggest that bacterial signals related to the bacterial ability to fix nitrogen, might be responsible for the regulation of HRGP expression in root nodules.
Publishing year
2002
Language
English
Pages
652-660
Publication/Series
Physiologia Plantarum
Volume
114
Issue
4
Links
Document type
Journal article
Publisher
John Wiley & Sons Inc.
Topic
- Biological Sciences
- Ecology
Status
Published
Research group
- Microbial Ecology
- Plant Biology
ISBN/ISSN/Other
- ISSN: 0031-9317