signal recognition particle

molecule

Also known as: SRP

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Last updated

July 13, 2026

Quick Summary

The signal recognition particle (SRP) is a complex of proteins and RNA that plays a crucial role in protein synthesis within eukaryotic cells. When a protein being synthesized has a specific "signal sequence," the SRP binds to it and halts further protein production. This binding targets the ribosome-mRNA-protein complex to the rough endoplasmic reticulum (RER) membrane. The SRP then dissociates, allowing protein synthesis to resume and the protein to thread through the RER membrane into the ER lumen for further processing, folding, and eventual transport to its designated location within or outside the cell.1

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The rough endoplasmic reticulum
…RNA molecule known as the signal recognition particle (SRP). The SRP also binds to the ribosome to halt further formation of the protein. The membrane of the ER contains receptor sites that bind the SRP-ribosome complex to the RER membrane. Upon binding, translation resumes, with the SRP dissociating from the…
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…RNA molecule known as the signal recognition particle (SRP). The SRP also binds to the ribosome to halt further formation of the protein. The membrane of the ER contains receptor sites that bind the SRP-ribosome complex to the RER membrane. Upon binding, translation resumes, with the SRP dissociating from the…
Read More