English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  The Chloroplast DnaJ Homolog CDJ1 of Chlamydomonas reinhardtii Is Part of a Multichaperone Complex Containing HSP70B, CGE1, and HSP90C

Willmund, F., Dorn, K. V., Schulz-Raffelt, M., & Schroda, M. (2008). The Chloroplast DnaJ Homolog CDJ1 of Chlamydomonas reinhardtii Is Part of a Multichaperone Complex Containing HSP70B, CGE1, and HSP90C. Plant Physiology, 148(4), 2070-2082. doi:10.​1104/​pp.​108.​127944.

Item is

Files

show Files
hide Files
:
Willmund-2008-The Chloroplast DnaJ.pdf (Any fulltext), 3MB
Name:
Willmund-2008-The Chloroplast DnaJ.pdf
Description:
-
OA-Status:
Visibility:
Public
MIME-Type / Checksum:
application/pdf / [MD5]
Technical Metadata:
Copyright Date:
-
Copyright Info:
-
License:
-

Locators

show

Creators

show
hide
 Creators:
Willmund, F.1, Author
Dorn, K. V.1, Author
Schulz-Raffelt, M.2, Author           
Schroda, M.2, Author           
Affiliations:
1External Organizations, ou_persistent22              
2Plant Molecular Chaperone Networks and Stress, Cooperative Research Groups, Max Planck Institute of Molecular Plant Physiology, Max Planck Society, ou_1753312              

Content

show
hide
Free keywords: escherichia-coli dnaj blue native electrophoresis membrane-protein complexes heat-shock proteins molecular chaperones chlorate-resistant crystal-structure j-domain in-vivo plastidic hsp70b
 Abstract: We report on the molecular and biochemical characterization of CDJ1, one of three zinc-finger-containing J-domain proteins encoded by the Chlamydomonas reinhardtii genome. Fractionation experiments indicate that CDJ1 is a plastidic protein. In the chloroplast, CDJ1 was localized to the soluble stroma fraction, but also to thylakoids and to low density membranes. Although the CDJ1 gene was strongly heat shock inducible, CDJ1 protein levels increased only slightly during heat shock. Cellular CDJ1 concentrations were close to those of heat shock protein 70B (HSP70B), the major HSP70 in the Chlamydomonas chloroplast. CDJ1 complemented the temperature-sensitive phenotype of an Escherichia coli mutant lacking its dnaJ gene and interacted with E. coli DnaK, hence classifying it as a bona fide DnaJ protein. In soluble cell extracts, CDJ1 was found to organize into stable dimers and into complexes of high molecular mass. Immunoprecipitation experiments revealed that CDJ1 forms common complexes with plastidic HSP90C, HSP70B, and CGE1. In blue native-polyacrylamide gel electrophoresis, all four (co) chaperones migrated at 40% to 90% higher apparent than calculated molecular masses, indicating that greatest care must be taken when molecular masses of protein complexes are estimated from their migration relative to standard native marker proteins. Immunoprecipitation experiments fromsize-fractioned soluble cell extracts suggested that HSP90C and HSP70B exist as preformed complex that is joined by CDJ1. In summary, CDJ1 and CGE1 are novel cohort proteins of the chloroplast HSP90-HSP70 multichaperone complex. As HSP70B, CDJ1, and CGE1 are derived from the endosymbiont, whereas HSP90C is of eukaryotic origin, we observe in the chloroplast the interaction of two chaperone systems of distinct evolutionary origin.

Details

show
hide
Language(s): eng - English
 Dates: 2008-10-222008
 Publication Status: Issued
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: -
 Identifiers: ISI: ISI:000261501500026
DOI: 10.​1104/​pp.​108.​127944
ISSN: 0032-0889 (Print) 0032-0889 (Linking)
URI: ://000261501500026 http://www.jstor.org/stable/pdfplus/40066329.pdf
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Plant Physiology
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: 148 (4) Sequence Number: - Start / End Page: 2070 - 2082 Identifier: -