Abstract
Signal recognition particle (SRP), together with its receptor (SR), mediates the targeting of ribosome-nascent chain complexes to the endoplasmic reticulum. Using protein cross-linking, we detected distinct modes in the binding of SRP to the ribosome. During signal peptide recognition, SRP54 is positioned at the exit site close to ribosomal proteins L23a and L35. When SRP54 contacts SR, SRP54 is rearranged such that it is no longer close to L23a. This repositioning may allow the translocon to dock with the ribosome, leading to insertion of the signal peptide into the translocation channel.
MeSH Terms
Animals
Centrifugation, Density Gradient
Cross-Linking Reagents
Dogs
Guanosine Diphosphate/metabolism,pharmacology
Guanosine Triphosphate/metabolism
Guanylyl Imidodiphosphate/metabolism,pharmacology
Models, Molecular
Plant Proteins/chemistry,metabolism
Precipitin Tests
Prolactin/genetics,metabolism
Protein Binding
Protein Precursors/genetics,metabolism
Protein Sorting Signals
Protein Transport
Receptors, Cytoplasmic and Nuclear/chemistry,metabolism
Receptors, Peptide/chemistry,metabolism
Ribosomal Proteins/chemistry,metabolism
Ribosomes/metabolism
Saccharomyces cerevisiae Proteins
Signal Recognition Particle/chemistry,metabolism
Succinimides
Chemicals
Cross-Linking Reagents
Plant Proteins
Protein Precursors
Protein Sorting Signals
RPL35A protein, S cerevisiae
Receptors, Cytoplasmic and Nuclear
Receptors, Peptide
Ribosomal Proteins
SRP54 protein, S cerevisiae
Saccharomyces cerevisiae Proteins
Signal Recognition Particle
Succinimides
signal peptide receptor
Guanosine Diphosphate
Guanylyl Imidodiphosphate
preprolactin
Guanosine Triphosphate
Prolactin
disuccinimidyl suberate
Authors & Affiliations
5 authors, click to expand affiliations / ORCID
Pool Martin R
Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), D-69120 Heidelberg, Germany. mrp@zmbh.uni-heidelberg.de
Stumm Joachim
Fulga Tudor A
Sinning Irmgard
Dobberstein Bernhard