Type III intermediate filaments as novel CoAlation targets.
Nuria Goya-Iglesias1, Bess Yi Kun Yu2, Ivan Gout2,3
1Department of Molecular and Cellular Biosciences, Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain.
Redox Report : Communications in Free Radical Research
|June 25, 2026
Summary
Coenzyme A modification (CoAlation) occurs in vimentin, GFAP, and desmin, influencing filament assembly. This reversible CoAlation may protect intermediate filaments from damaging oxidative stress.
Area of Science:
- Biochemistry
- Cell Biology
- Structural Biology
Background:
- Type III intermediate filaments (vimentin, GFAP, desmin) regulate cell mechanics and signaling.
- Posttranslational modifications (PTMs) tightly control intermediate filament function.
- A single cysteine residue in these monomers is crucial for network remodeling under oxidative stress.
Purpose of the Study:
- Investigate Coenzyme A modification (CoAlation) of vimentin, GFAP, and desmin.
- Determine the functional consequences of CoAlation on intermediate filaments.
Main Methods:
- In vitro CoAlation assessment using gel assays and immunological detection.
- Evaluation of vimentin filament assembly via electron microscopy.
- In-cell CoAlation analysis using immunofluorescence, proximity ligation assays, and immunoprecipitation.
Main Results:
- CoAlation of vimentin, GFAP, and desmin was observed both in vitro and in cellular models, enhanced by oxidants.
- CoAlation of vimentin influenced other thiol modifications, reducing disulfide-mediated oligomerization and alkylation.
- In vitro polymerization of vimentin in the presence of Coenzyme A resulted in shorter filaments.
Conclusions:
- Vimentin, GFAP, and desmin undergo CoAlation at their sole cysteine residues.
- CoAlation impacts filament assembly and competes with other cysteine modifications.
- The reversible nature of CoAlation suggests a potential protective role against irreversible oxidative damage.
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