Related Experiment Video
Updated: Jul 9, 2026

The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis
Published on: March 17, 2010
Multiple cysteine residues are implicated in Janus kinase 2-mediated catalysis
Naila M Mamoon1, John K Smith, Kiranam Chatti
1Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi 39216-4505, USA.
Oxidizing conditions inactivate Janus kinase 2 (JAK2) by affecting critical cysteine residues. Reducing these residues restores JAK2 activity, revealing a direct redox regulation mechanism.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Signaling
Background:
- The redox regulation of Janus kinase 2 (JAK2) is not well understood.
- Conflicting reports exist regarding JAK2's response to cellular oxidizing conditions.
Purpose of the Study:
- To investigate the role of cysteine residues in JAK2's redox regulation.
- To determine the mechanism by which oxidizing conditions affect JAK2 activity.
Main Methods:
- Utilized the baculoviral expression vector system to produce recombinant JAK2 variants.
- Employed cysteine-to-serine mutagenesis to alter specific cysteine residues.
- Analyzed the catalytic activity of wild-type and mutant JAK2 under varying redox conditions.
Main Results:
- JAK2 is catalytically inactive under oxidized conditions; activity is restored upon reduction.
- Four specific cysteine residues (Cys866, Cys917, Cys1094, Cys1105) in the catalytic domain are crucial for JAK2 activity.
- The amino-terminal autoinhibitory domain is not essential for direct redox regulation.
Conclusions:
- JAK2 activity is directly regulated by the oxidation and reduction of critical cysteine residues in its catalytic domain.
- These findings clarify the mechanism of JAK2 redox regulation, resolving previous contradictions.
More Related Videos
09:37Combining Non-reducing SDS-PAGE Analysis and Chemical Crosslinking to Detect Multimeric Complexes Stabilized by Disulfide Linkages in Mammalian Cells in Culture
Published on: May 2, 2019
07:16Resin-Assisted Capture Coupled with Isobaric Tandem Mass Tag Labeling for Multiplexed Quantification of Protein Thiol Oxidation
Published on: June 21, 2021
Related Concept Videos
The JAK-STAT Signaling Pathway
Caspases
Ligand Binding and Linkage
Covalently Linked Protein Regulators
These groups modify specific amino acids in a protein.
MAPK Signaling Cascades
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...