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. 1997 Aug;114(4):1477–1485. doi: 10.1104/pp.114.4.1477

Expression and native structure of cytosolic class II small heat-shock proteins.

K W Helm 1, G J Lee 1, E Vierling 1
PMCID: PMC158441  PMID: 9276957

Abstract

Higher plants synthesize small heat-shock proteins (smHSPs) from five related gene families. The class I and II families encode cytosolic smHSPs. We characterized the class II smHSPs of pea (Pisum sativum) and compared them with class I smHSPs. Antibodies against recombinant HSP17.7, a class II smHSP, recognized four heat-inducible 17- to 18-kD polypeptides and did not cross-react with class I smHSPs. On sucrose gradients the class II smHSPs sedimented primarily at 8 Svedberg units, indicating that they are components of large complexes similar in size to class I smHSP complexes. However, the class I and II complexes were readily distinguishable by nondenaturing polyacrylamide gel electrophoresis and isoelectric focusing. Nondenaturing immune precipitations using anti-HSP17.7 or anti-HSP18.1 (a class I smHSP) antiserum provide further evidence that the class I and II smHSPs exist in different complexes, composed primarily of smHSPs. Recombinant HSP17.7 and HSP18.1 formed complexes of sizes similar to those formed in vivo. When these two smHSPs were mixed, denatured with urea, and then dialyzed, the distinct class I and II complexes again formed, each containing only HSP18.1 or HSP17.7. Thus, cytosolic smHSPs from two related gene families expressed simultaneously form distinct complexes in vivo, suggesting that they have subtly different functions.

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Selected References

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  1. Atkinson B. G., Raizada M., Bouchard R. A., Frappier R. H., Walden D. B. The independent stage-specific expression of the 18-kDa heat shock protein genes during microsporogenesis in Zea mays L. Dev Genet. 1993;14(1):15–26. doi: 10.1002/dvg.1020140104. [DOI] [PubMed] [Google Scholar]
  2. Bednarek S. Y., Raikhel N. V. The barley lectin carboxyl-terminal propeptide is a vacuolar protein sorting determinant in plants. Plant Cell. 1991 Nov;3(11):1195–1206. doi: 10.1105/tpc.3.11.1195. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bouchard R. A. Characterization of expressed meiotic prophase repeat transcript clones of Lilium: meiosis-specific expression, relatedness, and affinities to small heat shock protein genes. Genome. 1990 Feb;33(1):68–79. doi: 10.1139/g90-012. [DOI] [PubMed] [Google Scholar]
  4. Buchner J. Supervising the fold: functional principles of molecular chaperones. FASEB J. 1996 Jan;10(1):10–19. [PubMed] [Google Scholar]
  5. Chen Q., Osteryoung K., Vierling E. A 21-kDa chloroplast heat shock protein assembles into high molecular weight complexes in vivo and in Organelle. J Biol Chem. 1994 May 6;269(18):13216–13223. [PubMed] [Google Scholar]
  6. Clos J., Brandau S. pJC20 and pJC40--two high-copy-number vectors for T7 RNA polymerase-dependent expression of recombinant genes in Escherichia coli. Protein Expr Purif. 1994 Apr;5(2):133–137. doi: 10.1006/prep.1994.1020. [DOI] [PubMed] [Google Scholar]
  7. Derocher A. E., Helm K. W., Lauzon L. M., Vierling E. Expression of a Conserved Family of Cytoplasmic Low Molecular Weight Heat Shock Proteins during Heat Stress and Recovery. Plant Physiol. 1991 Aug;96(4):1038–1047. doi: 10.1104/pp.96.4.1038. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Dietrich P. S., Bouchard R. A., Casey E. S., Sinibaldi R. M. Isolation and characterization of a small heat shock protein gene from maize. Plant Physiol. 1991 Aug;96(4):1268–1276. doi: 10.1104/pp.96.4.1268. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Garfin D. E. Isoelectric focusing. Methods Enzymol. 1990;182:459–477. doi: 10.1016/0076-6879(90)82037-3. [DOI] [PubMed] [Google Scholar]
  10. Helm K. W., LaFayette P. R., Nagao R. T., Key J. L., Vierling E. Localization of small heat shock proteins to the higher plant endomembrane system. Mol Cell Biol. 1993 Jan;13(1):238–247. doi: 10.1128/mcb.13.1.238. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Hopf N., Plesofsky-Vig N., Brambl R. The heat shock response of pollen and other tissues of maize. Plant Mol Biol. 1992 Jul;19(4):623–630. doi: 10.1007/BF00026788. [DOI] [PubMed] [Google Scholar]
  12. Horwitz J. Alpha-crystallin can function as a molecular chaperone. Proc Natl Acad Sci U S A. 1992 Nov 1;89(21):10449–10453. doi: 10.1073/pnas.89.21.10449. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Jakob U., Gaestel M., Engel K., Buchner J. Small heat shock proteins are molecular chaperones. J Biol Chem. 1993 Jan 25;268(3):1517–1520. [PubMed] [Google Scholar]
  14. Jinn T. L., Chen Y. M., Lin C. Y. Characterization and Physiological Function of Class I Low-Molecular-Mass, Heat-Shock Protein Complex in Soybean. Plant Physiol. 1995 Jun;108(2):693–701. doi: 10.1104/pp.108.2.693. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Kobayashi T., Kobayashi E., Sato S., Hotta Y., Miyajima N., Tanaka A., Tabata S. Characterization of cDNAs induced in meiotic prophase in lily microsporocytes. DNA Res. 1994;1(1):15–26. doi: 10.1093/dnares/1.1.15. [DOI] [PubMed] [Google Scholar]
  16. Krishna P., Felsheim R. F., Larkin J. C., Das A. Structure and Light-Induced Expression of a Small Heat-Shock Protein Gene of Pharbitis nil. Plant Physiol. 1992 Dec;100(4):1772–1779. doi: 10.1104/pp.100.4.1772. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  18. Lauzon L. M., Helm K. W., Vierling E. A cDNA clone from Pisum sativum encoding a low molecular weight heat shock protein. Nucleic Acids Res. 1990 Jul 25;18(14):4274–4274. doi: 10.1093/nar/18.14.4274. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Lavoie J. N., Gingras-Breton G., Tanguay R. M., Landry J. Induction of Chinese hamster HSP27 gene expression in mouse cells confers resistance to heat shock. HSP27 stabilization of the microfilament organization. J Biol Chem. 1993 Feb 15;268(5):3420–3429. [PubMed] [Google Scholar]
  20. Lee G. J., Pokala N., Vierling E. Structure and in vitro molecular chaperone activity of cytosolic small heat shock proteins from pea. J Biol Chem. 1995 May 5;270(18):10432–10438. doi: 10.1074/jbc.270.18.10432. [DOI] [PubMed] [Google Scholar]
  21. Merck K. B., Groenen P. J., Voorter C. E., de Haard-Hoekman W. A., Horwitz J., Bloemendal H., de Jong W. W. Structural and functional similarities of bovine alpha-crystallin and mouse small heat-shock protein. A family of chaperones. J Biol Chem. 1993 Jan 15;268(2):1046–1052. [PubMed] [Google Scholar]
  22. Nover L., Scharf K. D., Neumann D. Cytoplasmic heat shock granules are formed from precursor particles and are associated with a specific set of mRNAs. Mol Cell Biol. 1989 Mar;9(3):1298–1308. doi: 10.1128/mcb.9.3.1298. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Rollet E., Lavoie J. N., Landry J., Tanguay R. M. Expression of Drosophila's 27 kDa heat shock protein into rodent cells confers thermal resistance. Biochem Biophys Res Commun. 1992 May 29;185(1):116–120. doi: 10.1016/s0006-291x(05)80963-5. [DOI] [PubMed] [Google Scholar]
  24. Studier F. W., Rosenberg A. H., Dunn J. J., Dubendorff J. W. Use of T7 RNA polymerase to direct expression of cloned genes. Methods Enzymol. 1990;185:60–89. doi: 10.1016/0076-6879(90)85008-c. [DOI] [PubMed] [Google Scholar]

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