Efficient in vitro import of a cytosolic heat shock protein into pea chloroplasts
- 1 August 1986
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 83 (15), 5502-5506
- https://doi.org/10.1073/pnas.83.15.5502
Abstract
In order to further our understanding of the targeting of nuclear-encoded proteins into intracellular organelles, we have investigated the import of chimeric precursor proteins into pea chloroplasts. Two different chimeric precursor proteins were produced by in vitro expression of chimeric genes. One chimeric precursor contained the transit peptide of the small subunit of soybean ribulose 1,5-bisphosphate carboxylase and the mature peptide of the same protein from pea. The second contained the same transit peptide plus 13 amino acids of the pea mature peptide fused to a cytosolic heat shock protein. The extent of import and binding of the two chimeric proteins was examined by using quantitative assays and was compared to the import of pea small subunit precursor. Both precursor proteins imported well into pea chloroplasts, although the extent of import observed with the chimeric small-subunit-heat shock precursor was less than that observed with the soybean-pea small subumit precursor. The heat shock protein alone did not import into nor bind to chloroplasts. The binding of both the chimeric small-subunit-heat shock protein and the soybean-pea small subunit precursor to chloroplasts was physiologically significant, as shown by the fact that when chloroplasts with bound precursors were isolated, these bound precursors could subsequently be imported.This publication has 25 references indexed in Scilit:
- Upstream sequences required for efficient expression of a soybean heat shock gene.Molecular and Cellular Biology, 1986
- DNA sequence and transcript mapping of a soybean gene encoding a small heat shock proteinProceedings of the National Academy of Sciences, 1985
- Precursors to two nuclear-encoded chloroplast proteins bind to the outer envelope membrane before being imported into chloroplasts.Journal of Biological Chemistry, 1985
- Sequence of a genomic DNA clone for the small subunit of ribulose bis-phosphate carboxylase-oxygenase from tobaccoNucleic Acids Research, 1985
- Targeting of a foreign protein to chloroplasts by fusion to the transit peptide from the small subunit of ribulose 1,5-bisphosphate carboxylaseNature, 1985
- Functional determinants in transit sequences: import and partial maturation by vascular plant chloroplasts of the ribulose-1,5-bisphosphate carboxylase small subunit of Chlamydomonas.The Journal of cell biology, 1985
- The cleavable prepiece of an imported mitochondrial protein is sufficient to direct cytosolic dihydrofolate reductase into the mitochondrial matrixFEBS Letters, 1984
- Optimal conditions for post-translational uptake of proteins by isolated chloroplasts. In vitro synthesis and transport of plastocyanin, ferredoxin-NADP+ oxidoreductase, and fructose-1,6-bisphosphatase.Journal of Biological Chemistry, 1982
- Transport of proteins into mitochondria and chloroplasts.The Journal of cell biology, 1979
- A Rapid and Sensitive Method for the Quantitation of Microgram Quantities of Protein Utilizing the Principle of Protein-Dye BindingAnalytical Biochemistry, 1976