Related Experiment Video
Updated: Aug 3, 2026

Split-Ubiquitin Based Membrane Yeast Two-Hybrid (MYTH) System: A Powerful Tool For Identifying Protein-Protein Interactions
Published on: February 2, 2010
Interactions among subunits of the oligosaccharyltransferase complex
J Fu1, M Ren, G Kreibich
1Department of Cell Biology, New York Medical Center, New York, New York 10016, USA.
The oligosaccharyltransferase (OST) complex subunits interact to form its structure. This study identifies specific interactions, confirming Dad1 as a fourth subunit and revealing how ribophorin I and II associate with OST48.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- The oligosaccharyltransferase (OST) complex is crucial for protein glycosylation in the endoplasmic reticulum.
- Mammalian OST is composed of ribophorin I (RI), ribophorin II (RII), and OST48, with Dad1 suggested as a fourth subunit.
Purpose of the Study:
- To elucidate the structural organization of the mammalian OST complex by studying subunit interactions.
- To confirm the role of Dad1 as a subunit of the mammalian OST complex.
Main Methods:
- Yeast two-hybrid system to analyze protein-protein interactions.
- Biochemical assays to confirm interactions.
- Deletion analyses to map interaction domains.
Main Results:
- Luminal domains of RI and RII interact with the luminal domain of OST48.
- Specific subdomains of RI and RII interact with OST48.
- Dad1's cytoplasmic N-terminal region interacts with OST48's cytoplasmic tail, confirming its subunit status.
- Homotypic interaction between RI cytoplasmic domains suggests a role in oligomeric assembly.
Conclusions:
- Specific interactions between OST subunits define the complex's structure.
- Dad1 is confirmed as a component of the mammalian OST complex.
- Interactions identified provide insights into the assembly and function of the OST complex.
More Related Videos
05:28Demonstration of Heterologous Complexes formed by Golgi-Resident Type III Membrane Proteins using Split Luciferase Complementation Assay
Published on: September 10, 2020
07:22The Development and Application of Biophysical Assays for Evaluating Ternary Complex Formation Induced by Proteolysis Targeting Chimeras (PROTACS)
Published on: January 12, 2024
Related Concept Videos
Cooperative Allosteric Transitions
Protein Complexes with Interchangeable Parts
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...
Oligosaccharide Assembly
Multiple sugar molecules that may or may...
Protein Modifications in the RER
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal sequences.
Protein Complexes with Interchangeable Parts
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 Translocation Machinery on 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.