Abstract
Increased heat tolerance is most often associated with the synthesis of heat-shock proteins following pre-exposure to a nonlethal heat treatment. In this study, a bromegrass (Bromus inermis Leyss cv Manchar) cell suspension cultured in a medium containing 75 microM abscisic acid (ABA) without prior heat treatment had a 87% survival rate, as determined by regrowth analysis, following exposure to 42.5 degrees C for 120 min. In contrast, less than 1% of the control cells survived this heat treatment. The heat tolerance provided by treatment with 75 microM ABA was first evidenced after 4 d of culture and reached a maximum tolerance after 11 d of culture. Preincubation with sucrose partially increased the heat tolerance of control cells and rendered ABA-treated cells tolerant to 45 degrees C for 120 min (a completely lethal heat treatment for control cells). Comparative two-dimensional polyacrylamide gel electrophoresis of cellular protein isolated from heat-tolerant cells identified 43 ABA-responsive proteins of which 26 were heat stable (did not coagulate and remained soluble after 30 min at 90 degrees C). Eight heat-stable, ABA-responsive proteins ranging from 23 to 45 kD had similar N-terminal sequences. The ABA-responsive (43-20 kD), but none of the control heat-stable, proteins cross-reacted to varying degrees with a polyclonal antibody directed against a conserved, lysine-rich dehydrin sequence. A group of 20- to 30-kD heat-stable, ABA-responsive proteins cross-reacted with both the anti-dehydrin antibody and an antibody directed against a cold-responsive winter wheat protein (Wcs 120). In ABA-treated cells, there was a positive correlation between heat- and pH-induced coagulation of a cell-free homogenate and the heat tolerance of these cells. At 50 degrees C, control homogenates coagulated after 8 min, whereas cellular fractions from ABA-treated cells showed only marginal coagulation after 15 min. In protection assays, addition of heat-stable, ABA-responsive polypeptides to control fractions reduced the heat-induced coagulation of cell-free homogenates. Sucrose (8%) alone and control, heat-stable fractions enhanced the thermostability of control fractions, but the most protection was conferred by ABA-responsive, heat-stable proteins in combination with sucrose. These data suggest that stress-tolerance mechanisms may develop as a result of cooperative interactions between stress proteins and cell osmolytes, e.g. sucrose. Hypotheses are discussed implicating the role of these proteins and osmolytes in preventing coagulation and denaturation of cellular proteins and membranes.
Full Text
The Full Text of this article is available as a PDF (1.8 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Aebersold R. H., Teplow D. B., Hood L. E., Kent S. B. Electroblotting onto activated glass. High efficiency preparation of proteins from analytical sodium dodecyl sulfate-polyacrylamide gels for direct sequence analysis. J Biol Chem. 1986 Mar 25;261(9):4229–4238. [PubMed] [Google Scholar]
- Blackman S. A., Obendorf R. L., Leopold A. C. Maturation proteins and sugars in desiccation tolerance of developing soybean seeds. Plant Physiol. 1992 Sep;100(1):225–230. doi: 10.1104/pp.100.1.225. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chen H. H., Li P. H., Brenner M. L. Involvement of abscisic Acid in potato cold acclimation. Plant Physiol. 1983 Feb;71(2):362–365. doi: 10.1104/pp.71.2.362. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chen T. H., Gusta L. V. Abscisic Acid-induced freezing resistance in cultured plant cells. Plant Physiol. 1983 Sep;73(1):71–75. doi: 10.1104/pp.73.1.71. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Close T. J., Kortt A. A., Chandler P. M. A cDNA-based comparison of dehydration-induced proteins (dehydrins) in barley and corn. Plant Mol Biol. 1989 Jul;13(1):95–108. doi: 10.1007/BF00027338. [DOI] [PubMed] [Google Scholar]
- Close T. J., Lammers P. J. An osmotic stress protein of cyanobacteria is immunologically related to plant dehydrins. Plant Physiol. 1993 Mar;101(3):773–779. doi: 10.1104/pp.101.3.773. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Goday A., Sánchez-Martínez D., Gómez J., Puigdomènech P., Pagès M. Gene Expression in Developing Zea mays Embryos: Regulation by Abscisic Acid of a Highly Phosphorylated 23- to 25-kD Group of Proteins. Plant Physiol. 1988 Nov;88(3):564–569. doi: 10.1104/pp.88.3.564. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Heikkila J. J., Papp J. E., Schultz G. A., Bewley J. D. Induction of heat shock protein messenger RNA in maize mesocotyls by water stress, abscisic Acid, and wounding. Plant Physiol. 1984 Sep;76(1):270–274. doi: 10.1104/pp.76.1.270. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Iturriaga G., Schneider K., Salamini F., Bartels D. Expression of desiccation-related proteins from the resurrection plant Craterostigma plantagineum in transgenic tobacco. Plant Mol Biol. 1992 Nov;20(3):555–558. doi: 10.1007/BF00040614. [DOI] [PubMed] [Google Scholar]
- Jacobsen J. V., Shaw D. C. Heat-stable proteins and abscisic Acid action in barley aleurone cells. Plant Physiol. 1989 Dec;91(4):1520–1526. doi: 10.1104/pp.91.4.1520. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Larosa P. C., Handa A. K., Hasegawa P. M., Bressan R. A. Abscisic Acid accelerates adaptation of cultured tobacco cells to salt. Plant Physiol. 1985 Sep;79(1):138–142. doi: 10.1104/pp.79.1.138. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lin C., Thomashow M. F. A cold-regulated Arabidopsis gene encodes a polypeptide having potent cryoprotective activity. Biochem Biophys Res Commun. 1992 Mar 31;183(3):1103–1108. doi: 10.1016/s0006-291x(05)80304-3. [DOI] [PubMed] [Google Scholar]
- Minton K. W., Karmin P., Hahn G. M., Minton A. P. Nonspecific stabilization of stress-susceptible proteins by stress-resistant proteins: a model for the biological role of heat shock proteins. Proc Natl Acad Sci U S A. 1982 Dec;79(23):7107–7111. doi: 10.1073/pnas.79.23.7107. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pajot-Augy E. Comparative effects of cryosolvents on tubulin association, thermal stability, and binding of microtubule-associated proteins. Cryobiology. 1993 Jun;30(3):286–298. doi: 10.1006/cryo.1993.1027. [DOI] [PubMed] [Google Scholar]
- Peterson G. L. A simplification of the protein assay method of Lowry et al. which is more generally applicable. Anal Biochem. 1977 Dec;83(2):346–356. doi: 10.1016/0003-2697(77)90043-4. [DOI] [PubMed] [Google Scholar]
- 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]
- Skriver K., Mundy J. Gene expression in response to abscisic acid and osmotic stress. Plant Cell. 1990 Jun;2(6):503–512. doi: 10.1105/tpc.2.6.503. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yaffe M. B., Farr G. W., Miklos D., Horwich A. L., Sternlicht M. L., Sternlicht H. TCP1 complex is a molecular chaperone in tubulin biogenesis. Nature. 1992 Jul 16;358(6383):245–248. doi: 10.1038/358245a0. [DOI] [PubMed] [Google Scholar]