Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Post-translational Translocation of Proteins to the RER01:27

Post-translational Translocation of Proteins to the RER

A sizable fraction of proteins destined for ER are first synthesized in the cell cytosol and then transported across the ER membrane–a process called post-translational translocation. Similar to cotranslationally translocated proteins, these proteins also use the Sec translocon complex to enter the ER lumen.
Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...
Cotranslational Protein Translocation01:20

Cotranslational Protein Translocation

Translocation of proteins across membranes is an ancient process that occurs even in bacteria and archaebacteria. In fact, the components of the translocation machinery are still conserved between prokaryotes and eukaryotes.
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
Insertion of Single-pass Transmembrane Proteins in the RER01:26

Insertion of Single-pass Transmembrane Proteins in the RER

Integral membrane proteins are proteins adhered to the lipid bilayer of a cell organelle or membrane. They can be of two types: transmembrane integral proteins that span the lipid bilayer and monotopic proteins that are attached to either side of the membrane but do not pass through it.
Integral transmembrane proteins possess transmembrane and extra membrane domains. The transmembrane domains are primarily made of 20-25 hydrophobic amino acids arranged in a helical secondary confirmation. These...
Protein Translocation Machinery on the ER Membrane01:28

Protein Translocation Machinery on the ER Membrane

The translocon complex situated on the ER membrane is the main gateway for the protein secretory pathway. It facilitates the transport of nascent peptides into the ER lumen and their insertion into the ER membrane.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
Insertion of Multi-pass Transmembrane Proteins in the RER01:29

Insertion of Multi-pass Transmembrane Proteins in the RER

The rough ER membrane synthesizes, assembles, and embeds transmembrane proteins in diverse topologies. These proteins function as transporters or channels and can remain in the ER membrane or are sent to the Golgi complex, lysosome, and cell membrane.
The multipass transmembrane proteins are the type IV integral membrane proteins with multiple topogenic sequences determining their spatial arrangement in the ER membrane. Nearly all multipass proteins lack a cleavable signal sequence and use...
Role of ER in the Secretory Pathway01:17

Role of ER in the Secretory Pathway

Eukaryotic cells have a special pathway that enables communication between various intracellular membrane-bound compartments and also with the extracellular environment. This pathway is termed as the secretory pathway.
Components of the secretory pathway
About a third of proteins synthesized in the cell are sorted via the secretory route. They shuffle between different compartments in membrane-bound vesicles until they reach their final destination. The main intracellular compartments involved...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

HyperTRIBE identifies hepatic IGF2BP2/IMP2 targets <i>in vivo</i> and links IMP2 to autophagy.

NAR molecular medicine·2026
Same author

Targeted Radiopharmaceutical Therapy: Advances, Investment Dynamics, and Future Directions-Part 2.

Journal of nuclear medicine : official publication, Society of Nuclear Medicine·2026
Same author

Targeted Radiopharmaceutical Therapy: Advances, Investment Dynamics, and Future Directions-Part 1.

Journal of nuclear medicine : official publication, Society of Nuclear Medicine·2026
Same author

Are <sup>61</sup>Cu, <sup>64</sup>Cu, and <sup>67</sup>Cu Really Happening?

Journal of nuclear medicine : official publication, Society of Nuclear Medicine·2026
Same author

IGF2BP2 Deficiency in Macrophages Impairs Migration, Reprograms Metabolism, and Limits Tumor Progression.

International journal of biological sciences·2026
Same author

Hetero-oligomerization drives structural plasticity of eukaryotic peroxiredoxins.

Nature chemical biology·2026

Related Experiment Video

Updated: Jun 11, 2026

Visualization of Endoplasmic Reticulum Localized mRNAs in Mammalian Cells
10:24

Visualization of Endoplasmic Reticulum Localized mRNAs in Mammalian Cells

Published on: December 17, 2012

Protein translocation across the ER membrane.

Richard Zimmermann1, Susanne Eyrisch, Mazen Ahmad

  • 1Medical Biochemistry & Molecular Biology, Saarland University, D-66041 Homburg, Germany. bcrzim@uks.eu

Biochimica Et Biophysica Acta
|July 6, 2010
PubMed
Summary

Protein translocation into the endoplasmic reticulum (ER) is vital for protein biogenesis. The Sec61 complex, a key transport machinery, facilitates this process, impacting cellular function and disease.

More Related Videos

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles
13:16

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles

Published on: December 31, 2019

Live Cell Calcium Imaging Combined with siRNA Mediated Gene Silencing Identifies Ca2+ Leak Channels in the ER Membrane and their Regulatory Mechanisms
13:40

Live Cell Calcium Imaging Combined with siRNA Mediated Gene Silencing Identifies Ca2+ Leak Channels in the ER Membrane and their Regulatory Mechanisms

Published on: July 7, 2011

Related Experiment Videos

Last Updated: Jun 11, 2026

Visualization of Endoplasmic Reticulum Localized mRNAs in Mammalian Cells
10:24

Visualization of Endoplasmic Reticulum Localized mRNAs in Mammalian Cells

Published on: December 17, 2012

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles
13:16

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles

Published on: December 31, 2019

Live Cell Calcium Imaging Combined with siRNA Mediated Gene Silencing Identifies Ca2+ Leak Channels in the ER Membrane and their Regulatory Mechanisms
13:40

Live Cell Calcium Imaging Combined with siRNA Mediated Gene Silencing Identifies Ca2+ Leak Channels in the ER Membrane and their Regulatory Mechanisms

Published on: July 7, 2011

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Protein translocation into the endoplasmic reticulum (ER) is a fundamental process in eukaryotic cells.
  • This process is crucial for the biogenesis of extracellular and organelle proteins.
  • It shares mechanistic similarities with protein export in prokaryotes.

Purpose of the Study:

  • To elucidate the mechanisms of protein translocation into the ER.
  • To highlight the role of the Sec61 complex in this process.
  • To discuss the implications of recent findings in yeast, mammals, and Trypanosoma brucei.

Main Methods:

  • Comparative analysis of protein translocation mechanisms across different organisms (yeast, mammals, T. brucei).
  • Focus on the structure and function of the heterotrimeric Sec61 complex.
  • Investigation of co- and post-translational translocation pathways.

Main Results:

  • Protein translocation into the ER involves signal peptides and transport machinery.
  • The Sec61 complex acts as a signal peptide recognition site and polypeptide channel.
  • Ligands like signal peptides, ribosomes, and BiP regulate the Sec61 complex gating.

Conclusions:

  • The Sec61 complex is central to ER protein translocation, acting as a conserved gatekeeper.
  • Understanding these mechanisms offers insights into cellular function and potential medical applications.
  • Comparative studies reveal conserved and divergent aspects of protein transport machinery.