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

Base-Catalyzed Ring-Opening of Epoxides02:26

Base-Catalyzed Ring-Opening of Epoxides

10.9K
Due to their highly strained structures, epoxides can readily undergo ring-opening reactions through nucleophilic substitution, either in the presence of an acid or a base. The nucleophilic substitution reactions in the presence of acid are called acid-catalyzed ring-opening reactions, and nucleophilic substitution reactions in the presence of a base are called base-catalyzed ring-opening reactions. Epoxides undergo base-catalyzed ring-opening reactions in the presence of a strong nucleophile...
10.9K
Conservative Site-specific Recombination and Phase Variation02:53

Conservative Site-specific Recombination and Phase Variation

7.3K
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
7.3K
Regulated Protein Degradation02:58

Regulated Protein Degradation

9.1K
It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
9.1K
Acid-Catalyzed Ring-Opening of Epoxides02:24

Acid-Catalyzed Ring-Opening of Epoxides

9.7K
Epoxides that are three-membered ring systems are more reactive than other cyclic and acyclic ethers. The high reactivity of epoxides originates from the strain present in the ring. This ring strain acts as a driving force for epoxides to undergo ring-opening reactions either with halogen acids or weak nucleophiles in the presence of mild acid. The acid catalyst converts the epoxide oxygen, a poor leaving group, into an oxonium ion, a better leaving group, making the reaction feasible. The...
9.7K
Enzymes and Activation Energy01:13

Enzymes and Activation Energy

24.6K
The activation energy (or free energy of activation), abbreviated as Ea, is the small amount of energy input necessary for all chemical reactions to occur. During chemical reactions, certain chemical bonds break, and new ones form. For example, when a glucose molecule breaks down, bonds between the molecule's carbon atoms break. Since these are energy-storing bonds, they release energy when broken. However, the molecule must be somewhat contorted to get into a state that allows the bonds to...
24.6K
The Proteasome Structure01:17

The Proteasome Structure

2.1K
The ubiquitin-proteasome pathway is a well-known mechanism utilized by eukaryotic cells to remove cytoplasmic proteins that are misfolded, damaged, or no longer needed. In this pathway, the protein that needs to be eliminated undergoes a process called ubiquitination, where a chain of ubiquitin molecules is attached to the 48th lysine residue of the target protein. This ubiquitin modification helps the proteasome distinguish between a target protein and a healthy protein.
The proteasome is an...
2.1K

You might also read

Related Articles

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

Sort by
Same author

The E3-ome gene-centric compendium reveals the human E3 ligase landscape.

Cell·2026
Same author

Structural basis for a nucleoporin exportin complex between RanBP2, SUMO1-RanGAP1, the E2 Ubc9, Crm1 and the Ran GTPase.

Nature communications·2025
Same author

Structural basis for a nucleoporin exportin complex between RanBP2, SUMO1-RanGAP1, the E2 Ubc9, Crm1 and the Ran GTPase.

bioRxiv : the preprint server for biology·2025
Same author

Chemical Tools for Probing the Ub/Ubl Conjugation Cascades.

Chembiochem : a European journal of chemical biology·2024
Same author

Structural basis for transthiolation intermediates in the ubiquitin pathway.

Nature·2024
Same author

An antibody that inhibits TGF-β1 release from latent extracellular matrix complexes attenuates the progression of renal fibrosis.

Science signaling·2024
Same journal

Daily briefing: How cooperation built the world.

Nature·2026
Same journal

Deep-sea oddities and boatloads of other new species - June's best science images.

Nature·2026
Same journal

From cloning to gene-editing: the enduring legacy of Dolly the sheep.

Nature·2026
Same journal

Time to give hydration breaks the red card? What science says about keeping cool.

Nature·2026
Same journal

Universities are relying on AI-detection software to catch cheating. How well do the programs work?

Nature·2026
Same journal

Daily briefing: 'Cyborg' cockroaches breathe underwater with printed suit.

Nature·2026
See all related articles

Related Experiment Video

Updated: Mar 16, 2026

Functional Characterization of RING-Type E3 Ubiquitin Ligases In Vitro and In Planta
10:27

Functional Characterization of RING-Type E3 Ubiquitin Ligases In Vitro and In Planta

Published on: December 5, 2019

9.4K

Capturing a substrate in an activated RING E3/E2-SUMO complex.

Frederick C Streich, Christopher D Lima

    Nature
    |August 12, 2016
    PubMed
    Summary
    This summary is machine-generated.

    Researchers elucidated how E3 ligases alter E2 enzyme specificity for post-translational protein modification. This structural insight reveals how E3 ligases direct substrates to E2 active sites for ubiquitination and SUMOylation.

    More Related Videos

    In Vitro SUMOylation Assay to Study SUMO E3 Ligase Activity
    09:45

    In Vitro SUMOylation Assay to Study SUMO E3 Ligase Activity

    Published on: January 29, 2018

    9.8K
    In Vitro Analysis of E3 Ubiquitin Ligase Function
    06:06

    In Vitro Analysis of E3 Ubiquitin Ligase Function

    Published on: May 14, 2021

    6.1K

    Related Experiment Videos

    Last Updated: Mar 16, 2026

    Functional Characterization of RING-Type E3 Ubiquitin Ligases In Vitro and In Planta
    10:27

    Functional Characterization of RING-Type E3 Ubiquitin Ligases In Vitro and In Planta

    Published on: December 5, 2019

    9.4K
    In Vitro SUMOylation Assay to Study SUMO E3 Ligase Activity
    09:45

    In Vitro SUMOylation Assay to Study SUMO E3 Ligase Activity

    Published on: January 29, 2018

    9.8K
    In Vitro Analysis of E3 Ubiquitin Ligase Function
    06:06

    In Vitro Analysis of E3 Ubiquitin Ligase Function

    Published on: May 14, 2021

    6.1K

    Area of Science:

    • Biochemistry
    • Molecular Biology
    • Structural Biology

    Background:

    • Post-translational protein modification by ubiquitin (Ub) and ubiquitin-like (Ubl) proteins regulates critical cellular processes.
    • Proliferating cell nuclear antigen (PCNA) is modified by Ub or SUMO at specific lysine residues to mediate DNA repair and cell cycle control.

    Purpose of the Study:

    • To elucidate the structural basis of substrate recognition and modification by E3/E2-Ubl complexes.
    • To understand how E3 ligases like Siz1 can alter E2 enzyme specificity for target lysine residues on substrates like PCNA.

    Main Methods:

    • Utilized an engineered E2 protein and cross-linking strategies to stabilize E3/E2-Ubl/substrate complexes.
    • Employed structural determination techniques to visualize the complex interactions.

    Main Results:

    • Captured a snapshot of an E3/E2–Ubl/substrate complex, revealing the mechanism of E3-mediated substrate targeting.
    • Demonstrated how E3 ligases can override E2 specificity to facilitate substrate lysine modification.

    Conclusions:

    • The study provides a structural mechanism for how E3 ligases dictate substrate specificity in ubiquitination and SUMOylation pathways.
    • This work offers insights into the regulation of PCNA modification and its role in DNA damage response.