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.

摘要: Many polypeptides translated in the cytosol enter chloroplast where they assemble into macromolecular complexes. The transport of these plastid can be examined vitro by mixing isolated chloroplasts with pea poly(A) RNA translation products. Following optimization both wheat germ system and conditions during uptake, we observe post-translational over 100 polypeptides; many remain soluble phase organelle while others integrate thylakoid membranes. Most products transported co-migrate vivo on sodium dodecyl sulfate-polyacrylamide gels. Furthermore, improved conditions, demonstrate plastocyanin, ferredoxin-NADP+ oxidoreductase, fructose-1,6-bisphosphatase plastids. While have not been able to detect any cell-free product that is immunologically related fructose-1,6-bisphosphatase, plastocyanin oxidoreductase are synthesized as precursors vitro. These imported processed size their mature counterparts. As determined gel electrophoresis, molecular weight precursor 15,000 larger than 8,000 product.