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

The Proteasome01:13

The Proteasome

817
Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
817
Covalently Linked Protein Regulators02:04

Covalently Linked Protein Regulators

6.8K
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein....
6.8K
Regulated Protein Degradation02:58

Regulated Protein Degradation

7.2K
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...
7.2K
The Proteasome Structure01:17

The Proteasome Structure

716
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...
716
Protein Complexes with Interchangeable Parts01:57

Protein Complexes with Interchangeable Parts

2.5K
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...
2.5K
Export of Misfolded Proteins out of the ER01:32

Export of Misfolded Proteins out of the ER

3.5K
After folding, the ER assesses the quality of secretory and membrane proteins. The correctly folded proteins are cleared by the calnexin cycle for transport to their final destination, while misfolded proteins are held back in the ER lumen. The ER chaperones attempt to unfold and refold the misfolded proteins but sometimes fail to achieve the correct native conformation. Such terminally misfolded proteins are then exported to the cytosol by ER-associated degradation or ERAD pathway for...
3.5K

You might also read

Related Articles

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

Sort by
Same author

Nucleotides act as 'molecular glue' and can sense their own abundance.

Nature·2026
Same author

The ubiquitin-proteasome system and autophagy as guardians of the cellular proteome.

FEBS letters·2026
Same author

PSG6: A mitochondrially-targeted gentisic acid derivative exerts antiplatelet action via mitochondrial complex I inhibition.

Redox biology·2026
Same author

TBK1 restricts IRGQ-mediated autophagy.

Nature communications·2026
Same author

Intracellular lipopolysaccharide binds RETREG1/FAM134B to regulate ER remodeling upon bacterial infection.

Autophagy·2026
Same author

Discovery and Development of a Potent LIMK2 Isoform-Specific Degrader.

ACS chemical biology·2026

Related Experiment Video

Updated: Jun 11, 2025

Ubiquitin Chain Analysis by Parallel Reaction Monitoring
08:33

Ubiquitin Chain Analysis by Parallel Reaction Monitoring

Published on: June 17, 2020

3.5K

Ubiquitous ubiquitin: From bacteria to eukaryotes.

Mohit Misra1, Ivan Ðikić2

  • 1Institute of Biochemistry II, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue Straße 15, 60438 Frankfurt am Main, Germany.

Structure (London, England : 1993)
|October 4, 2024
PubMed
Summary

Researchers discovered ubiquitin-like machinery in bacteria, challenging the belief it was exclusive to archaea and eukaryotes. This finding reveals a widespread bacterial system later adopted by eukaryotes for protein regulation.

More Related Videos

In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
11:36

In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones

Published on: July 25, 2019

10.7K
Evaluation of Substrate Ubiquitylation by E3 Ubiquitin-ligase in Mammalian Cell Lysates
09:47

Evaluation of Substrate Ubiquitylation by E3 Ubiquitin-ligase in Mammalian Cell Lysates

Published on: May 10, 2022

2.5K

Related Experiment Videos

Last Updated: Jun 11, 2025

Ubiquitin Chain Analysis by Parallel Reaction Monitoring
08:33

Ubiquitin Chain Analysis by Parallel Reaction Monitoring

Published on: June 17, 2020

3.5K
In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
11:36

In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones

Published on: July 25, 2019

10.7K
Evaluation of Substrate Ubiquitylation by E3 Ubiquitin-ligase in Mammalian Cell Lysates
09:47

Evaluation of Substrate Ubiquitylation by E3 Ubiquitin-ligase in Mammalian Cell Lysates

Published on: May 10, 2022

2.5K

Area of Science:

  • Molecular Biology
  • Biochemistry
  • Structural Biology

Background:

  • Ubiquitin and ubiquitin-like proteins are crucial for protein regulation in eukaryotes and archaea.
  • Previously, the presence of such protein modification systems in bacteria was not widely recognized.

Purpose of the Study:

  • To investigate the existence and nature of ubiquitin-like systems in bacteria.
  • To understand the evolutionary origins and functional implications of these systems.

Main Methods:

  • Bioinformatic analysis of bacterial genomes.
  • Biochemical assays to characterize protein interactions.
  • X-ray crystallography to determine the structure of bacterial ubiquitin-like proteins.

Main Results:

  • Identification of a novel ubiquitin-like modification system in bacteria.
  • Structural and functional similarities between bacterial and eukaryotic ubiquitin-like systems were revealed.
  • Evidence suggests this bacterial system predates its eukaryotic counterpart.

Conclusions:

  • The ubiquitin-like protein modification system is not exclusive to archaea and eukaryotes but is also present in bacteria.
  • This discovery provides new insights into the evolution of protein regulation pathways.
  • The findings suggest that eukaryotes may have adopted this ancient bacterial machinery for diverse cellular functions, including protein degradation.