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

Rab Cascades01:25

Rab Cascades

Rab GTPases act in a regulated cascade during membrane fusion, helping the lipid bilayers mix. The Rab family of proteins are active when bound to GTP, and inactive when bound to GDP. Hence, they act as guanine nucleotide-dependent molecular switches. Rab-GTP recognizes and binds to long or short-range tethering proteins to capture the target vesicle. These tethers coordinate with SNAREs on the vesicle and the target membrane to assemble the trans SNARE complex that locks the mixing bilayers.
Rab Proteins01:14

Rab Proteins

Rab proteins constitute the largest family of monomeric GTPases, of which 70 members are present in humans. Rab proteins and their effectors regulate consecutive stages of vesicle transport such as vesicle transport, docking, and fusion to the correct recipient membrane.
Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
Protein Complex Assembly02:41

Protein Complex Assembly

Proteins can form homomeric complexes with another unit of the same protein or heteromeric complexes with different types.  Most protein complexes self-assemble spontaneously via ordered pathways, while some proteins need assembly factors that guide their proper assembly. Despite the crowded intracellular environment, proteins usually interact with their correct partners and form functional complexes.
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Protein Complex Assembly02:41

Protein Complex Assembly

Proteins can form homomeric complexes with another unit of the same protein or heteromeric complexes with different types.  Most protein complexes self-assemble spontaneously via ordered pathways, while some proteins need assembly factors that guide their proper assembly. Despite the crowded intracellular environment, proteins usually interact with their correct partners and form functional complexes.
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Protein Complexes with Interchangeable Parts01:57

Protein Complexes with Interchangeable Parts

Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
Protein Complexes with Interchangeable Parts01:57

Protein Complexes with Interchangeable Parts

Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...

You might also read

Related Articles

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

Sort by
Same author

Atg18 interaction positions Atg2 for efficient lipid transfer into phagophore elongation.

The EMBO journal·2026
Same author

Endosomal maturation is controlled by the trimeric Bulli-Mon1-Ccz1 Rab7 GEF complex and the Rab5 GTPase-activating protein GAPsec.

Journal of cell science·2026
Same author

Structuring of the yeast endolysosomal pathway by the Rab5 guanine nucleotide exchange factors Muk1 and Vps9.

Molecular biology of the cell·2026
Same author

Endolysosomal transport at the crossroads of cellular signaling.

Trends in cell biology·2026
Same author

Getting to the right place at the right time - membrane trafficking and maturation in the endolysosomal system.

Biological chemistry·2025
Same author

Peptidyl-tRNA hydrolase 2 is a negative regulator of peripartum cardiomyopathy with heart failure in female mice.

Nature communications·2025

Related Experiment Video

Updated: Jun 11, 2026

Combining Chemical Cross-linking and Mass Spectrometry of Intact Protein Complexes to Study the Architecture of Multi-subunit Protein Assemblies
10:01

Combining Chemical Cross-linking and Mass Spectrometry of Intact Protein Complexes to Study the Architecture of Multi-subunit Protein Assemblies

Published on: November 28, 2017

Defined subunit arrangement and rab interactions are required for functionality of the HOPS tethering complex.

Clemens W Ostrowicz1, Cornelia Bröcker, Franziska Ahnert

  • 1Department of Biology, Biochemistry Section, University of Osnabrück, Barbarastrasse 13, 49076 Osnabrück, Germany.

Traffic (Copenhagen, Denmark)
|July 8, 2010
PubMed
Summary

Two homologous tethering complexes, CORVET and HOPS, share similar structures and functions in eukaryotic vesicle transport. Their subunit interchangeability suggests distinct yet related assembly pathways for cellular membrane trafficking.

More Related Videos

Purification and Quality Control of Recombinant Septin Complexes for Cell-Free Reconstitution
11:50

Purification and Quality Control of Recombinant Septin Complexes for Cell-Free Reconstitution

Published on: June 23, 2022

Expression, Purification, and Liposome Binding of Budding Yeast SNX-BAR Heterodimers
10:28

Expression, Purification, and Liposome Binding of Budding Yeast SNX-BAR Heterodimers

Published on: December 6, 2019

Related Experiment Videos

Last Updated: Jun 11, 2026

Combining Chemical Cross-linking and Mass Spectrometry of Intact Protein Complexes to Study the Architecture of Multi-subunit Protein Assemblies
10:01

Combining Chemical Cross-linking and Mass Spectrometry of Intact Protein Complexes to Study the Architecture of Multi-subunit Protein Assemblies

Published on: November 28, 2017

Purification and Quality Control of Recombinant Septin Complexes for Cell-Free Reconstitution
11:50

Purification and Quality Control of Recombinant Septin Complexes for Cell-Free Reconstitution

Published on: June 23, 2022

Expression, Purification, and Liposome Binding of Budding Yeast SNX-BAR Heterodimers
10:28

Expression, Purification, and Liposome Binding of Budding Yeast SNX-BAR Heterodimers

Published on: December 6, 2019

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Multisubunit tethering complexes and Rab-GTPases coordinate vesicle tethering and fusion within the endomembrane system.
  • The endosomal CORVET and vacuolar HOPS complexes are homologous hexameric tethering complexes crucial for cellular transport.

Purpose of the Study:

  • To investigate the structural and functional similarities between the CORVET and HOPS tethering complexes.
  • To elucidate the assembly pathways and potential subunit interchangeability of these complexes.

Main Methods:

  • Comparative analysis of subunit topologies of CORVET and HOPS complexes.
  • Reconstitution of HOPS complex activity using purified subcomplexes.
  • Investigation of binding interactions between core components like Vps11, Vps39, and Vps3.

Main Results:

  • CORVET and HOPS complexes exhibit similar hexameric topologies with Rab-binding proteins at one end and Vps33 at the other.
  • HOPS complex activity can be reconstituted but requires all six subunits.
  • Vps11 acts as a central connector, binding both HOPS Vps39 and CORVET Vps3 via the same site.
  • HOPS Vps39 is also present on endosomes, suggesting functional overlap.

Conclusions:

  • The findings suggest a conserved mechanism for membrane bridging involving Rab-GTP and SNARE binding.
  • CORVET and HOPS complexes likely follow distinct but related assembly pathways.
  • Subunit interchangeability may allow for dynamic transitions between tethering complex functions.