PMID:9305630
| Citation |
Powers, T and Walter, P (1997) Co-translational protein targeting catalyzed by the Escherichia coli signal recognition particle and its receptor. EMBO J. 16:4880-6 |
|---|---|
| Abstract |
The Ffh-4.5S ribonucleoprotein particle (RNP) and FtsY from Escherichia coli are homologous to essential components of the mammalian signal recognition particle (SRP) and SRP receptor, respectively. The ability of these E. coli components to function in a bona fide co-translational targeting pathway remains unclear. Here we demonstrate that the Ffh-4.5S RNP and FtsY can efficiently replace their mammalian counterparts in targeting nascent secretory proteins to microsomal membranes in vitro. Targeting in the heterologous system requires a hydrophobic signal sequence, utilizes GTP and, moreover, occurs co-translationally. Unlike mammalian SRP, however, the Ffh-4.5S RNP is unable to arrest translational elongation, which results in a narrow time window for the ribosome nascent chain to interact productively with the membrane-bound translocation machinery. The highly negatively charged N-terminal domain of FtsY, which is a conserved feature among prokaryotic SRP receptor homologs, is important for translocation and acts to localize the protein to the membrane. Our data illustrate the extreme functional conservation between prokaryotic and eukaryotic SRP and SRP receptors and suggest that the basic mechanism of co-translational protein targeting is conserved between bacteria and mammals. |
| Links |
PubMed PMC1170123 Online version:10.1093/emboj/16.16.4880 |
| Keywords |
Animals; Bacterial Proteins/chemistry; Bacterial Proteins/metabolism; Biological Transport; Dogs; Electrophoresis, Polyacrylamide Gel; Endoplasmic Reticulum/metabolism; Escherichia coli/chemistry; Escherichia coli/genetics; Escherichia coli Proteins; Guanosine Triphosphate/metabolism; Membrane Proteins/metabolism; Microsomes/metabolism; Pancreas; Peptide Chain Elongation, Translational/physiology; Peptides/metabolism; Prolactin/metabolism; Protein Biosynthesis; Protein Precursors/metabolism; Protein Processing, Post-Translational/physiology; Proteins/metabolism; Receptors, Cytoplasmic and Nuclear/chemistry; Receptors, Cytoplasmic and Nuclear/metabolism; Receptors, Peptide/metabolism; Signal Recognition Particle/metabolism; beta-Lactamases/metabolism |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
<annotationlinks/>
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
References
See Help:References for how to manage references in EcoliWiki.