Labile disulfide bonds are common at the leucocyte cell surface
Clive Metcalfe1, Peter Cresswell, Laura Ciaccia
1Sir William Dunn School of Pathology, University of Oxford , Oxford OX1 3RE, UK.
Open Biology
|May 31, 2012
Summary
Researchers identified common redox-labile disulfide bonds in leukocyte membrane proteins. This suggests a widespread
Area of Science:
- Biochemistry
- Cell Biology
- Proteomics
Background:
- Redox conditions fluctuate during immune responses and viral infections.
- Biochemical effects of redox changes on cell-surface proteins are poorly understood.
- Some disulfide bonds in membrane proteins are labile, while others are structurally critical and less exposed.
Purpose of the Study:
- To develop and apply a proteomic method to identify redox-labile disulfide bonds in leukocyte cell-surface proteins.
- To characterize the biochemical consequences of changing redox conditions on membrane proteins.
Main Methods:
- Proteomic and mass spectrometry techniques were employed.
- Screening for non-structural, redox-labile disulfide bonds in leucocyte cell-surface proteins.
- Utilized different reducing conditions and enzymes like thioredoxin.
Main Results:
- Identified common labile disulfide bonds in several classes of leukocyte membrane proteins.
- Around 30 membrane proteins, including integrins, receptors, and transporters, were regularly identified.
- Mass spectrometry confirmed cysteine residue modification in many identified proteins.
Conclusions:
- Widespread modulation of membrane protein activity by a 'redox regulator' mechanism is implied.
- Functional changes are predicted for proteins such as integrins and cytokine receptors.
- The findings suggest significant impacts on enzymes, adhesion proteins, and transporters.
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