JBC

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 QUICK SEARCH:   [advanced]


     


Originally published In Press as doi:10.1074/jbc.M306684200 on September 10, 2003

J. Biol. Chem., Vol. 278, Issue 47, 46473-46481, November 21, 2003
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
278/47/46473    most recent
M306684200v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Rial, D. V.
Right arrow Articles by Ceccarelli, E. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Rial, D. V.
Right arrow Articles by Ceccarelli, E. A.
Social Bookmarking
 Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?

Precursors with Altered Affinity for Hsp70 in Their Transit Peptides Are Efficiently Imported into Chloroplasts*

Daniela V. Rial{ddagger}, Jorgelina Ottado§, and Eduardo A. Ceccarelli§

From the Molecular Biology Division, Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Argentina

Protein import into chloroplasts is postulated to occur with the involvement of molecular chaperones. We have determined that the transit peptide of ferredoxin-NADP(H) reductase precursor binds preferentially to an Hsp70 from chloroplast stroma. To investigate the role of Hsp70 molecular chaperones in chloroplast protein import, we analyzed the import into pea chloroplasts of preproteins with decreased Hsp70 binding affinity in their transit peptides. Our results indicate that the precursor with the lowest affinity for Hsp70 molecular chaperones in its transit peptide was imported to chloroplasts with similar apparent Km as the wild type precursor and a 2-fold increase in Vmax. Thus, a strong interaction between chloroplast stromal Hsp70 and the transit peptide seems not to be essential for protein import. These results indicate that in chloroplasts the main unfolding force during protein import may be applied by molecular chaperones other than Hsp70s. Although stromal Hsp70s undoubtedly participate in chloroplast biogenesis, the role of these molecular chaperones in chloroplast protein translocation differs from the one proposed in the mechanisms postulated up to date.


Received for publication, June 24, 2003 , and in revised form, September 9, 2003.

The nucleotide sequence(s) reported in this paper has been submitted to the GenBankTM/EBI Data Bank with accession number(s) AF241251, AF241252, and AF241253.

* This study was supported in part by grants from the International Foundation for Science (Sweden), the Fundación Antorchas, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), and the Agencia de Promoción Científica y Tecnológica (Argentina). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

{ddagger} A Fellow of the CONICET, Argentina.

§ Staff members of the CONICET, Argentina.

To whom correspondence should be addressed. Tel.: 54-341-435-1235; Fax: 54-341-439-0465; E-mail: cecca{at}arnet.com.ar.


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?


This article has been cited by other articles:


Home page
Plant Physiol.Home page
P.-H. Su and H.-m. Li
Arabidopsis Stromal 70-kD Heat Shock Proteins Are Essential for Plant Development and Important for Thermotolerance of Germinating Seeds
Plant Physiology, March 1, 2008; 146(3): 1231 - 1241.
[Abstract] [Full Text] [PDF]


Home page
J. Biol. Chem.Home page
T. Martin, R. Sharma, C. Sippel, K. Waegemann, J. Soll, and U. C. Vothknecht
A Protein Kinase Family in Arabidopsis Phosphorylates Chloroplast Precursor Proteins
J. Biol. Chem., December 29, 2006; 281(52): 40216 - 40223.
[Abstract] [Full Text] [PDF]


Home page
J. Virol.Home page
Y. Xiang, K. Kakani, R. Reade, E. Hui, and D. Rochon
A 38-amino-Acid sequence encompassing the arm domain of the cucumber necrosis virus coat protein functions as a chloroplast transit Peptide in infected plants.
J. Virol., August 1, 2006; 80(16): 7952 - 7964.
[Abstract] [Full Text] [PDF]


Home page
Plant Physiol.Home page
D. Constan, J. E. Froehlich, S. Rangarajan, and K. Keegstra
A Stromal Hsp100 Protein Is Required for Normal Chloroplast Development and Function in Arabidopsis
Plant Physiology, November 1, 2004; 136(3): 3605 - 3615.
[Abstract] [Full Text] [PDF]




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 All ASBMB Journals   Molecular and Cellular Proteomics 
 Journal of Lipid Research   ASBMB Today 
Copyright © 2003 by the American Society for Biochemistry and Molecular Biology.