Abstract
Mild trypsin treatment of Spirodela oligorrhiza thylakoid membranes leads to partial digestion of the rapidly metabolized, surface-exposed, 32,000-dalton protein. Under these conditions, photoreduction of ferricyanide becomes insensitive to diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea], an inhibitor of photosystem II electron transport. Preincubation of thylakoids with diuron leads to a conformational change in the 32,000-dalton protein, modifying its trypsin digestion and preventing expression of diuron insensitivity. Finally, light affects the susceptibility of the 32,000-dalton protein to digestion by trypsin. In other experiments, thylakoids specifically depleted in the 32,000-dalton protein were found to be deficient in electron transport at the reducing side of photosystem II but not at the oxidizing side or in photosystem I activities. Thus, the rapidly metabolized 32,000-dalton thylakoid protein in Spirodela chloroplasts fulfills the requirements of the hypothesized "proteinaceous shield" [Renger, G. (1976) Biochim. Biophys. Acta 440, 287-300] regulating electron flow through photosystem II and mediating diuron sensitivity.
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Selected References
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- Arnon D. I. COPPER ENZYMES IN ISOLATED CHLOROPLASTS. POLYPHENOLOXIDASE IN BETA VULGARIS. Plant Physiol. 1949 Jan;24(1):1–15. doi: 10.1104/pp.24.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Arntzen C. J., Ditto C. L., Brewer P. E. Chloroplast membrane alterations in triazine-resistant Amaranthus retroflexus biotypes. Proc Natl Acad Sci U S A. 1979 Jan;76(1):278–282. doi: 10.1073/pnas.76.1.278. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blair G. E., Ellis R. J. Protein synthesis in chloroplasts. I. Light-driven synthesis of the large subunit of fraction I protein by isolated pea chloroplasts. Biochim Biophys Acta. 1973 Aug 24;319(2):223–234. doi: 10.1016/0005-2787(73)90013-0. [DOI] [PubMed] [Google Scholar]
- Burke J. J., Ditto C. L., Arntzen C. J. Involvement of the light-harvesting complex in cation regulation of excitation energy distribution in chloroplasts. Arch Biochem Biophys. 1978 Apr 15;187(1):252–263. doi: 10.1016/0003-9861(78)90031-0. [DOI] [PubMed] [Google Scholar]
- Carter D. P., Staehelin L. A. Proteolysis of chloroplast thylakoid membranes. II. Evidence for the involvement of the light-harvesting chlorophyll a/b-protein complex in thylakoid stacking and for effects of magnesium ions on photosystem II-light-harvesting complex aggregates in the absence of membrane stacking. Arch Biochem Biophys. 1980 Apr 1;200(2):374–386. doi: 10.1016/0003-9861(80)90367-7. [DOI] [PubMed] [Google Scholar]
- Chua N. H., Gillham N. W. The sites of synthesis of the principal thylakoid membrane polypeptides in Chlamydomonas reinhardtii. J Cell Biol. 1977 Aug;74(2):441–452. doi: 10.1083/jcb.74.2.441. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Croze E., Kelly M., Horton P. Loss of sensitivity to diuron after trypsin digestion of chloroplast photosystem II particles. FEBS Lett. 1979 Jul 1;103(1):22–26. doi: 10.1016/0014-5793(79)81242-9. [DOI] [PubMed] [Google Scholar]
- Grebanier A. E., Coen D. M., Rich A., Bogorad L. Membrane proteins synthesized but not processed by isolated maize chloroplasts. J Cell Biol. 1978 Sep;78(3):734–746. doi: 10.1083/jcb.78.3.734. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Leto K. J., Miles D. Characterization of Three Photosystem II Mutants in Zea mays L. Lacking a 32,000 Dalton Lamellar Polypeptide. Plant Physiol. 1980 Jul;66(1):18–24. doi: 10.1104/pp.66.1.18. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pfister K., Radosevich S. R., Arntzen C. J. Modification of Herbicide Binding to Photosystem II in Two Biotypes of Senecio vulgaris L. Plant Physiol. 1979 Dec;64(6):995–999. doi: 10.1104/pp.64.6.995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Regitz G., Ohad I. Trypsin-sensitive photosynthetic activities in chloroplast membranes from Chlamydomonas reinhardi, y-1. J Biol Chem. 1976 Jan 10;251(1):247–252. [PubMed] [Google Scholar]
- Renger G. Studies on the structural and functional organization of system II of photosynthesis. The use of trypsin as a structurally selective inhibitor at the outer surface of the thylakoid membrane. Biochim Biophys Acta. 1976 Aug 13;440(2):287–300. doi: 10.1016/0005-2728(76)90063-3. [DOI] [PubMed] [Google Scholar]
- Silverthorne J., Ellis R. J. Protein synthesis in chloroplasts. VIII. Differential synthesis of chloroplast proteins during spinach leaf development. Biochim Biophys Acta. 1980 Apr 30;607(2):319–330. doi: 10.1016/0005-2787(80)90084-2. [DOI] [PubMed] [Google Scholar]
- Steinback K. E., Burke J. J., Arntzen C. J. Evidence for the role of surface-exposed segments of the light-harvesting complex in cation-mediated control of chloroplast structure and function. Arch Biochem Biophys. 1979 Jul;195(2):546–557. doi: 10.1016/0003-9861(79)90381-3. [DOI] [PubMed] [Google Scholar]
- Weinbaum S. A., Gressel J., Reisfeld A., Edelman M. Characterization of the 32,000 Dalton Chloroplast Membrane Protein: III. Probing Its Biological Function in Spirodela. Plant Physiol. 1979 Nov;64(5):828–832. doi: 10.1104/pp.64.5.828. [DOI] [PMC free article] [PubMed] [Google Scholar]