Home LiteratureArticle Details
PMID: 9118955 Published · ppublish English Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

Stable association of chloroplastic precursors with protein translocation complexes that contain proteins from both envelope membranes and a stromal Hsp100 molecular chaperone.

The EMBO journal ·Vol. 16 ·No. 5 ·1997-03-03 ·Pages 935-46

Nielsen E, Akita M, Davila-Aponte J, Keegstra K

Abstract

Cytoplasmically synthesized precursors interact with translocation components in both the outer and inner envelope membranes during transport into chloroplasts. Using co-immunoprecipitation techniques, with antibodies specific to known translocation components, we identified stable interactions between precursor proteins and their associated membrane translocation components in detergent-solubilized chloroplastic membrane fractions. Antibodies specific to the outer envelope translocation components OEP75 and OEP34, the inner envelope translocation component IEP110 and the stromal Hsp100, ClpC, specifically co-immunoprecipitated precursor proteins under limiting ATP conditions, a stage we have called docking. A portion of these same translocation components was co-immunoprecipitated as a complex, and could also be detected by co-sedimentation through a sucrose density gradient. ClpC was observed only in complexes with those precursors utilizing the general import apparatus, and its interaction with precursor-containing translocation complexes was destabilized by ATP. Finally, ClpC was co-immunoprecipitated with a portion of the translocation components of both outer and inner envelope membranes, even in the absence of added precursors. We discuss possible roles for stromal Hsp100 in protein import and mechanisms of precursor binding in chloroplasts.

MeSH Terms
Adenosine Triphosphate/pharmacology Chloroplasts/metabolism Detergents/pharmacology Electrophoresis, Polyacrylamide Gel Heat-Shock Proteins/metabolism Histone-Lysine N-Methyltransferase/metabolism Immunoblotting Membrane Proteins/chemistry,metabolism Molecular Chaperones/metabolism Peas/metabolism Plant Proteins/metabolism Precipitin Tests Protein Binding Protein Precursors/metabolism
Chemicals
Detergents Heat-Shock Proteins IEP110 protein, Pisum sativum Membrane Proteins Molecular Chaperones OEP75 protein precursor, plant Plant Proteins Protein Precursors Adenosine Triphosphate ribulose-1,5-bisphosphate carboxylase-oxygenase large subunit epsilonN-methyltransferase Histone-Lysine N-Methyltransferase
Authors & Affiliations
4 authors, click to expand affiliations / ORCID
Nielsen E
MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing 48824, USA.
Akita M
Davila-Aponte J
Keegstra K
References (47)
47 references, click to expand
  1. Mitochondrial protein import: biochemical and genetic evidence for interaction of matrix hsp70 and the inner membrane protein MIM44.
    J Cell Biol. 1994 Dec;127(6 Pt 1):1547-56 PMID: 7798311
  2. The binding of precursor proteins to chloroplasts requires nucleoside triphosphates in the intermembrane space.
    J Biol Chem. 1992 Jan 5;267(1):433-9 PMID: 1730608
  3. ATP is required for the binding of precursor proteins to chloroplasts.
    J Biol Chem. 1989 Apr 25;264(12):6724-9 PMID: 2708339
  4. A new chloroplast protein import intermediate reveals distinct translocation machineries in the two envelope membranes: energetics and mechanistic implications.
    J Cell Biol. 1996 Jan;132(1-2):63-75 PMID: 8567731
  5. Protein import into chloroplasts requires a chloroplast ATPase.
    Proc Natl Acad Sci U S A. 1987 May;84(10):3288-92 PMID: 2953027
  6. Cleavage of structural proteins during the assembly of the head of bacteriophage T4.
    Nature. 1970 Aug 15;227(5259):680-5 PMID: 5432063
  7. Mitochondrial Hsp70/MIM44 complex facilitates protein import.
    Nature. 1994 Oct 27;371(6500):768-74 PMID: 7935837
  8. Sequence and structure of Clp P, the proteolytic component of the ATP-dependent Clp protease of Escherichia coli.
    J Biol Chem. 1990 Jul 25;265(21):12536-45 PMID: 2197275
  9. Kinetic analysis of the transport of thylakoid lumenal proteins in experiments using intact chloroplasts.
    J Biol Chem. 1991 Mar 25;266(9):5884-90 PMID: 2005124
  10. The mitochondrial protein import machinery. Role of ATP in dissociation of the Hsp70.Mim44 complex.
    J Biol Chem. 1995 Dec 15;270(50):29848-53 PMID: 8530381
  11. The ClpX heat-shock protein of Escherichia coli, the ATP-dependent substrate specificity component of the ClpP-ClpX protease, is a novel molecular chaperone.
    EMBO J. 1995 May 1;14(9):1867-77 PMID: 7743994
  12. Identification of intermediates in the pathway of protein import into chloroplasts and their localization to envelope contact sites.
    J Cell Biol. 1993 Jan;120(1):103-15 PMID: 8416981
  13. NH2-terminal amino acid sequences of precursor and mature forms of the ribulose-1,5-bisphosphate carboxylase small subunit from Chlamydomonas reinhardtii.
    J Cell Biol. 1979 Dec;83(3):615-22 PMID: 521455
  14. A molecular chaperone, ClpA, functions like DnaK and DnaJ.
    Proc Natl Acad Sci U S A. 1994 Dec 6;91(25):12218-22 PMID: 7991609
  15. Current views on chloroplast protein import and hypotheses on the origin of the transport mechanism.
    J Bioenerg Biomembr. 1990 Dec;22(6):789-810 PMID: 2092038
  16. Isolation and characterization of a cDNA clone encoding a cognate 70-kDa heat shock protein of the chloroplast envelope.
    J Biol Chem. 1992 Feb 15;267(5):2986-93 PMID: 1371110
  17. Hsp78, a Clp homologue within mitochondria, can substitute for chaperone functions of mt-hsp70.
    EMBO J. 1995 Jul 17;14(14):3434-44 PMID: 7628444
  18. Early events in the import/assembly pathway of an integral thylakoid protein.
    Eur J Biochem. 1990 Nov 26;194(1):33-42 PMID: 2253622
  19. A receptor component of the chloroplast protein translocation machinery.
    Science. 1994 Dec 23;266(5193):1989-92 PMID: 7801125
  20. The Clp proteins: proteolysis regulators or molecular chaperones?
    J Bacteriol. 1992 Feb;174(4):1081-5 PMID: 1735703
  21. Requirement for hsp70 in the mitochondrial matrix for translocation and folding of precursor proteins.
    Nature. 1990 Nov 8;348(6297):137-43 PMID: 2234077
  22. Two components of the chloroplast protein import apparatus, IAP86 and IAP75, interact with the transit sequence during the recognition and translocation of precursor proteins at the outer envelope.
    J Cell Biol. 1996 Jul;134(2):315-27 PMID: 8707818
  23. Internal ATP is the only energy requirement for the translocation of precursor proteins across chloroplastic membranes.
    J Biol Chem. 1989 Apr 25;264(12):6730-6 PMID: 2708340
  24. Post-translational transport into intact chloroplasts of a precursor to the small subunit of ribulose-1,5-bisphosphate carboxylase.
    Proc Natl Acad Sci U S A. 1978 Dec;75(12):6110-4 PMID: 16592597
  25. Sequential action of mitochondrial chaperones in protein import into the matrix.
    EMBO J. 1991 Nov;10(11):3273-80 PMID: 1915294
  26. A constituent of the chloroplast import complex represents a new type of GTP-binding protein.
    Plant J. 1995 Mar;7(3):401-11 PMID: 7757113
  27. Isolation of components of the chloroplast protein import machinery.
    Science. 1994 Nov 11;266(5187):1007-12 PMID: 7973649
  28. Precursors to two nuclear-encoded chloroplast proteins bind to the outer envelope membrane before being imported into chloroplasts.
    J Biol Chem. 1985 Mar 25;260(6):3691-6 PMID: 3882712
  29. Characterization of a cDNA clone encoding a chloroplast-targeted Clp homologue.
    Plant Mol Biol. 1993 Feb;21(3):525-37 PMID: 8443344
  30. Molecular dissection of the mechanism of protein import into chloroplasts.
    Cold Spring Harb Symp Quant Biol. 1995;60:629-36 PMID: 8824436
  31. Dynamic interaction of the protein translocation systems in the inner and outer membranes of yeast mitochondria.
    EMBO J. 1995 May 15;14(10):2293-7 PMID: 7774587
  32. Protein folding in the cell.
    Nature. 1992 Jan 2;355(6355):33-45 PMID: 1731198
  33. A component of the chloroplastic protein import apparatus is targeted to the outer envelope membrane via a novel pathway.
    EMBO J. 1995 Jun 1;14(11):2436-46 PMID: 7781598
  34. Identification of two GTP-binding proteins in the chloroplast protein import machinery.
    Science. 1994 Nov 11;266(5187):1035-9 PMID: 7973656
  35. Functional independence of the protein translocation machineries in mitochondrial outer and inner membranes: passage of preproteins through the intermembrane space.
    EMBO J. 1993 May;12(5):2211-8 PMID: 8491208
  36. The essential yeast protein MIM44 (encoded by MPI1) is involved in an early step of preprotein translocation across the mitochondrial inner membrane.
    Mol Cell Biol. 1993 Dec;13(12):7364-71 PMID: 8246957
  37. Immunoblotting and dot immunobinding--current status and outlook.
    J Immunol Methods. 1984 Sep 4;72(2):313-40 PMID: 6206159
  38. The stroma of higher plant plastids contain ClpP and ClpC, functional homologs of Escherichia coli ClpP and ClpA: an archetypal two-component ATP-dependent protease.
    Plant Cell. 1995 Oct;7(10):1713-22 PMID: 7580259
  39. Protein translocation across chloroplast envelope membranes.
    Trends Cell Biol. 1995 Jun;5(6):243-7 PMID: 14732129
  40. Common principles of protein translocation across membranes.
    Science. 1996 Mar 15;271(5255):1519-26 PMID: 8599107
  41. A precursor protein partly translocated into yeast mitochondria is bound to a 70 kd mitochondrial stress protein.
    EMBO J. 1990 Dec;9(13):4315-22 PMID: 2265609
  42. Protease Ti, a new ATP-dependent protease in Escherichia coli, contains protein-activated ATPase and proteolytic functions in distinct subunits.
    J Biol Chem. 1988 Jun 25;263(18):8727-34 PMID: 2967816
  43. Envelope membrane proteins that interact with chloroplastic precursor proteins.
    Plant Cell. 1994 Jan;6(1):93-105 PMID: 8130644
  44. Dynamic interaction between Isp45 and mitochondrial hsp70 in the protein import system of the yeast mitochondrial inner membrane.
    Proc Natl Acad Sci U S A. 1994 Dec 20;91(26):12818-22 PMID: 7809127
  45. Targeting of proteins to the outer envelope membrane uses a different pathway than transport into chloroplasts.
    Plant Cell. 1991 Jul;3(7):709-17 PMID: 1841725
  46. Shedding light on the chloroplast protein import machinery.
    Cell. 1995 Nov 17;83(4):521-4 PMID: 7585953
  47. Topology of IEP110, a component of the chloroplastic protein import machinery present in the inner envelope membrane.
    EMBO J. 1996 Aug 15;15(16):4230-8 PMID: 8861951
Article Info
Journal
The EMBO journal
Abbr.
EMBO J
ISSN
0261-4189
DOI
10.1093/emboj/16.5.935
Published
1997-03-03
Pages
935-46
Language
English
Region
England
NLM ID
8208664
PMCID
PMC1169694
Subset
IM
External Links
PubMed source DOI: 10.1093/emboj/16.5.935 PMC Full Text View journal details
Analysis Services
Analysis Services

Contact

No. 2 Wenbo Road, Zhangqiu District, Jinan, Shandong

Qilu Normal University · Genelibs Bioinformatics Lab

750 Shunhua Rd, Jinan

2F, Bldg F, University Science Park

Tel: 0531-88819269

WeChat Official Account

Follow our WeChat subscription account for real-time updates and the latest in medical and biological research.


Business Email

E-mail: [email protected]

Copyright © 2026.Genelibs Jinan Honghui Biotechnology Co., Ltd. 鲁ICP备20007159号-2