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. 1995 Jul 17;14(14):3434–3444. doi: 10.1002/j.1460-2075.1995.tb07349.x

Hsp78, a Clp homologue within mitochondria, can substitute for chaperone functions of mt-hsp70.

M Schmitt 1, W Neupert 1, T Langer 1
PMCID: PMC394410  PMID: 7628444

Abstract

Hsp78 is a Clp homologue within mitochondria of Saccharomyces cerevisiae. Deletion of HSP78 does not cause any detectable changes in wild type cells, but results in a petite phenotype in the ssc1-3 mutant strain carrying a temperature-sensitive allele of mt-hsp70. When overexpressed in the ssc1-3 mutant strain, hsp78 suppresses the defect in mitochondrial protein import under permissive conditions in vitro and interacts directly with newly imported polypeptide chains. As a molecular chaperone, hsp78 prevents the aggregation of misfolded proteins in the matrix of mitochondria under conditions of impaired mt-hsp70 function. However, unlike misfolded proteins associated with mt-hsp70, hsp78-bound polypeptides are not efficiently degraded by the ATP-dependent PIM1 protease. Thus, hsp78 can partially substitute for mt-hsp70 functions in the assembly of mitochondria and may be part of a salvage pathway if mt-hsp70 is limiting.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Brandt A. Pulse labeling of yeast cells as a tool to study mitochondrial protein import. Methods Cell Biol. 1991;34:369–376. doi: 10.1016/s0091-679x(08)61691-x. [DOI] [PubMed] [Google Scholar]
  2. Craig E. A., Kramer J., Shilling J., Werner-Washburne M., Holmes S., Kosic-Smithers J., Nicolet C. M. SSC1, an essential member of the yeast HSP70 multigene family, encodes a mitochondrial protein. Mol Cell Biol. 1989 Jul;9(7):3000–3008. doi: 10.1128/mcb.9.7.3000. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Cyr D. M., Stuart R. A., Neupert W. A matrix ATP requirement for presequence translocation across the inner membrane of mitochondria. J Biol Chem. 1993 Nov 15;268(32):23751–23754. [PubMed] [Google Scholar]
  4. Daum G., Gasser S. M., Schatz G. Import of proteins into mitochondria. Energy-dependent, two-step processing of the intermembrane space enzyme cytochrome b2 by isolated yeast mitochondria. J Biol Chem. 1982 Nov 10;257(21):13075–13080. [PubMed] [Google Scholar]
  5. Gambill B. D., Voos W., Kang P. J., Miao B., Langer T., Craig E. A., Pfanner N. A dual role for mitochondrial heat shock protein 70 in membrane translocation of preproteins. J Cell Biol. 1993 Oct;123(1):109–117. doi: 10.1083/jcb.123.1.109. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Glick B. S. Can Hsp70 proteins act as force-generating motors? Cell. 1995 Jan 13;80(1):11–14. doi: 10.1016/0092-8674(95)90444-1. [DOI] [PubMed] [Google Scholar]
  7. Glick B. S., Wachter C., Reid G. A., Schatz G. Import of cytochrome b2 to the mitochondrial intermembrane space: the tightly folded heme-binding domain makes import dependent upon matrix ATP. Protein Sci. 1993 Nov;2(11):1901–1917. doi: 10.1002/pro.5560021112. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Goldberg A. L. The mechanism and functions of ATP-dependent proteases in bacterial and animal cells. Eur J Biochem. 1992 Jan 15;203(1-2):9–23. doi: 10.1111/j.1432-1033.1992.tb19822.x. [DOI] [PubMed] [Google Scholar]
  9. Gottesman S., Clark W. P., Maurizi M. R. The ATP-dependent Clp protease of Escherichia coli. Sequence of clpA and identification of a Clp-specific substrate. J Biol Chem. 1990 May 15;265(14):7886–7893. [PubMed] [Google Scholar]
  10. Gottesman S., Clark W. P., de Crecy-Lagard V., Maurizi M. R. ClpX, an alternative subunit for the ATP-dependent Clp protease of Escherichia coli. Sequence and in vivo activities. J Biol Chem. 1993 Oct 25;268(30):22618–22626. [PubMed] [Google Scholar]
  11. Gottesman S., Maurizi M. R. Regulation by proteolysis: energy-dependent proteases and their targets. Microbiol Rev. 1992 Dec;56(4):592–621. doi: 10.1128/mr.56.4.592-621.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Gottesman S., Squires C., Pichersky E., Carrington M., Hobbs M., Mattick J. S., Dalrymple B., Kuramitsu H., Shiroza T., Foster T. Conservation of the regulatory subunit for the Clp ATP-dependent protease in prokaryotes and eukaryotes. Proc Natl Acad Sci U S A. 1990 May;87(9):3513–3517. doi: 10.1073/pnas.87.9.3513. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Herrmann J. M., Stuart R. A., Craig E. A., Neupert W. Mitochondrial heat shock protein 70, a molecular chaperone for proteins encoded by mitochondrial DNA. J Cell Biol. 1994 Nov;127(4):893–902. doi: 10.1083/jcb.127.4.893. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Hill J., Donald K. A., Griffiths D. E., Donald G. DMSO-enhanced whole cell yeast transformation. Nucleic Acids Res. 1991 Oct 25;19(20):5791–5791. doi: 10.1093/nar/19.20.5791. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Hwang B. J., Woo K. M., Goldberg A. L., Chung C. H. 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):8727–8734. [PubMed] [Google Scholar]
  16. Kang P. J., Ostermann J., Shilling J., Neupert W., Craig E. A., Pfanner N. Requirement for hsp70 in the mitochondrial matrix for translocation and folding of precursor proteins. Nature. 1990 Nov 8;348(6297):137–143. doi: 10.1038/348137a0. [DOI] [PubMed] [Google Scholar]
  17. Katayama Y., Gottesman S., Pumphrey J., Rudikoff S., Clark W. P., Maurizi M. R. The two-component, ATP-dependent Clp protease of Escherichia coli. Purification, cloning, and mutational analysis of the ATP-binding component. J Biol Chem. 1988 Oct 15;263(29):15226–15236. [PubMed] [Google Scholar]
  18. Keller J. A., Simon L. D. Divergent effects of a dnaK mutation on abnormal protein degradation in Escherichia coli. Mol Microbiol. 1988 Jan;2(1):31–41. doi: 10.1111/j.1365-2958.1988.tb00004.x. [DOI] [PubMed] [Google Scholar]
  19. Kitagawa M., Wada C., Yoshioka S., Yura T. Expression of ClpB, an analog of the ATP-dependent protease regulatory subunit in Escherichia coli, is controlled by a heat shock sigma factor (sigma 32). J Bacteriol. 1991 Jul;173(14):4247–4253. doi: 10.1128/jb.173.14.4247-4253.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Kronidou N. G., Oppliger W., Bolliger L., Hannavy K., Glick B. S., Schatz G., Horst M. 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):12818–12822. doi: 10.1073/pnas.91.26.12818. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Leonhardt S. A., Fearson K., Danese P. N., Mason T. L. HSP78 encodes a yeast mitochondrial heat shock protein in the Clp family of ATP-dependent proteases. Mol Cell Biol. 1993 Oct;13(10):6304–6313. doi: 10.1128/mcb.13.10.6304. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Maarse A. C., Blom J., Grivell L. A., Meijer M. MPI1, an essential gene encoding a mitochondrial membrane protein, is possibly involved in protein import into yeast mitochondria. EMBO J. 1992 Oct;11(10):3619–3628. doi: 10.1002/j.1460-2075.1992.tb05446.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Manning-Krieg U. C., Scherer P. E., Schatz G. Sequential action of mitochondrial chaperones in protein import into the matrix. EMBO J. 1991 Nov;10(11):3273–3280. doi: 10.1002/j.1460-2075.1991.tb04891.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Neupert W., Hartl F. U., Craig E. A., Pfanner N. How do polypeptides cross the mitochondrial membranes? Cell. 1990 Nov 2;63(3):447–450. doi: 10.1016/0092-8674(90)90437-j. [DOI] [PubMed] [Google Scholar]
  25. Pajic A., Tauer R., Feldmann H., Neupert W., Langer T. Yta10p is required for the ATP-dependent degradation of polypeptides in the inner membrane of mitochondria. FEBS Lett. 1994 Oct 17;353(2):201–206. doi: 10.1016/0014-5793(94)01046-3. [DOI] [PubMed] [Google Scholar]
  26. Parsell D. A., Kowal A. S., Singer M. A., Lindquist S. Protein disaggregation mediated by heat-shock protein Hsp104. Nature. 1994 Dec 1;372(6505):475–478. doi: 10.1038/372475a0. [DOI] [PubMed] [Google Scholar]
  27. Parsell D. A., Sanchez Y., Stitzel J. D., Lindquist S. Hsp104 is a highly conserved protein with two essential nucleotide-binding sites. Nature. 1991 Sep 19;353(6341):270–273. doi: 10.1038/353270a0. [DOI] [PubMed] [Google Scholar]
  28. Pfanner N., Meijer M. Protein sorting. Pulling in the proteins. Curr Biol. 1995 Feb 1;5(2):132–135. doi: 10.1016/s0960-9822(95)00033-9. [DOI] [PubMed] [Google Scholar]
  29. Rassow J., Hartl F. U., Guiard B., Pfanner N., Neupert W. Polypeptides traverse the mitochondrial envelope in an extended state. FEBS Lett. 1990 Nov 26;275(1-2):190–194. doi: 10.1016/0014-5793(90)81469-5. [DOI] [PubMed] [Google Scholar]
  30. Rassow J., Maarse A. C., Krainer E., Kübrich M., Müller H., Meijer M., Craig E. A., Pfanner N. 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):1547–1556. doi: 10.1083/jcb.127.6.1547. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Ryan K. R., Menold M. M., Garrett S., Jensen R. E. SMS1, a high-copy suppressor of the yeast mas6 mutant, encodes an essential inner membrane protein required for mitochondrial protein import. Mol Biol Cell. 1994 May;5(5):529–538. doi: 10.1091/mbc.5.5.529. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Sanchez Y., Lindquist S. L. HSP104 required for induced thermotolerance. Science. 1990 Jun 1;248(4959):1112–1115. doi: 10.1126/science.2188365. [DOI] [PubMed] [Google Scholar]
  33. Sanchez Y., Parsell D. A., Taulien J., Vogel J. L., Craig E. A., Lindquist S. Genetic evidence for a functional relationship between Hsp104 and Hsp70. J Bacteriol. 1993 Oct;175(20):6484–6491. doi: 10.1128/jb.175.20.6484-6491.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Sanchez Y., Taulien J., Borkovich K. A., Lindquist S. Hsp104 is required for tolerance to many forms of stress. EMBO J. 1992 Jun;11(6):2357–2364. doi: 10.1002/j.1460-2075.1992.tb05295.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Schneider H. C., Berthold J., Bauer M. F., Dietmeier K., Guiard B., Brunner M., Neupert W. Mitochondrial Hsp70/MIM44 complex facilitates protein import. Nature. 1994 Oct 27;371(6500):768–774. doi: 10.1038/371768a0. [DOI] [PubMed] [Google Scholar]
  36. Schwarz E., Seytter T., Guiard B., Neupert W. Targeting of cytochrome b2 into the mitochondrial intermembrane space: specific recognition of the sorting signal. EMBO J. 1993 Jun;12(6):2295–2302. doi: 10.1002/j.1460-2075.1993.tb05883.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Sherman MYu, Goldberg A. L. Involvement of the chaperonin dnaK in the rapid degradation of a mutant protein in Escherichia coli. EMBO J. 1992 Jan;11(1):71–77. doi: 10.1002/j.1460-2075.1992.tb05029.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Squires C. L., Pedersen S., Ross B. M., Squires C. ClpB is the Escherichia coli heat shock protein F84.1. J Bacteriol. 1991 Jul;173(14):4254–4262. doi: 10.1128/jb.173.14.4254-4262.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Squires C., Squires C. L. The Clp proteins: proteolysis regulators or molecular chaperones? J Bacteriol. 1992 Feb;174(4):1081–1085. doi: 10.1128/jb.174.4.1081-1085.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Straus D. B., Walter W. A., Gross C. A. Escherichia coli heat shock gene mutants are defective in proteolysis. Genes Dev. 1988 Dec;2(12B):1851–1858. doi: 10.1101/gad.2.12b.1851. [DOI] [PubMed] [Google Scholar]
  41. Stuart R. A., Cyr D. M., Craig E. A., Neupert W. Mitochondrial molecular chaperones: their role in protein translocation. Trends Biochem Sci. 1994 Feb;19(2):87–92. doi: 10.1016/0968-0004(94)90041-8. [DOI] [PubMed] [Google Scholar]
  42. Stuart R. A., Gruhler A., van der Klei I., Guiard B., Koll H., Neupert W. The requirement of matrix ATP for the import of precursor proteins into the mitochondrial matrix and intermembrane space. Eur J Biochem. 1994 Feb 15;220(1):9–18. doi: 10.1111/j.1432-1033.1994.tb18593.x. [DOI] [PubMed] [Google Scholar]
  43. Suzuki C. K., Suda K., Wang N., Schatz G. Requirement for the yeast gene LON in intramitochondrial proteolysis and maintenance of respiration. Science. 1994 Apr 8;264(5156):273–276. doi: 10.1126/science.8146662. [DOI] [PubMed] [Google Scholar]
  44. Söllner T., Rassow J., Pfanner N. Analysis of mitochondrial protein import using translocation intermediates and specific antibodies. Methods Cell Biol. 1991;34:345–358. doi: 10.1016/s0091-679x(08)61689-1. [DOI] [PubMed] [Google Scholar]
  45. Thompson M. W., Maurizi M. R. Activity and specificity of Escherichia coli ClpAP protease in cleaving model peptide substrates. J Biol Chem. 1994 Jul 8;269(27):18201–18208. [PubMed] [Google Scholar]
  46. Tobias J. W., Shrader T. E., Rocap G., Varshavsky A. The N-end rule in bacteria. Science. 1991 Nov 29;254(5036):1374–1377. doi: 10.1126/science.1962196. [DOI] [PubMed] [Google Scholar]
  47. Ungermann C., Neupert W., Cyr D. M. The role of Hsp70 in conferring unidirectionality on protein translocation into mitochondria. Science. 1994 Nov 18;266(5188):1250–1253. doi: 10.1126/science.7973708. [DOI] [PubMed] [Google Scholar]
  48. Van Dyck L., Pearce D. A., Sherman F. PIM1 encodes a mitochondrial ATP-dependent protease that is required for mitochondrial function in the yeast Saccharomyces cerevisiae. J Biol Chem. 1994 Jan 7;269(1):238–242. [PubMed] [Google Scholar]
  49. Wagner I., Arlt H., van Dyck L., Langer T., Neupert W. Molecular chaperones cooperate with PIM1 protease in the degradation of misfolded proteins in mitochondria. EMBO J. 1994 Nov 1;13(21):5135–5145. doi: 10.1002/j.1460-2075.1994.tb06843.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  50. Wickner S., Gottesman S., Skowyra D., Hoskins J., McKenney K., Maurizi M. R. A molecular chaperone, ClpA, functions like DnaK and DnaJ. Proc Natl Acad Sci U S A. 1994 Dec 6;91(25):12218–12222. doi: 10.1073/pnas.91.25.12218. [DOI] [PMC free article] [PubMed] [Google Scholar]
  51. Wojtkowiak D., Georgopoulos C., Zylicz M. Isolation and characterization of ClpX, a new ATP-dependent specificity component of the Clp protease of Escherichia coli. J Biol Chem. 1993 Oct 25;268(30):22609–22617. [PubMed] [Google Scholar]
  52. Woo K. M., Kim K. I., Goldberg A. L., Ha D. B., Chung C. H. The heat-shock protein ClpB in Escherichia coli is a protein-activated ATPase. J Biol Chem. 1992 Oct 5;267(28):20429–20434. [PubMed] [Google Scholar]

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