Does Vimentin filaments rearrangement in response to oxidative stress serve as a redox sensor? If yes, could perturbing vimentin alter/impair redox sensing?
Evidence from recent biomedical research indicates that vimentin intermediate filaments (IFs) function as a dynamic redox sensor and sentinel network within the cell (Direct, High; PMID: 39079387, PMID: 37989035). This sensing capability is primarily mediated by a single, highly conserved cysteine residue (C328), which undergoes specific post-translational modifications (PTMs) in response to oxidative and electrophilic stress, leading to a profound morphological rearrangement of the vimentin network (Direct, High; PMID: 32255262, PMID: 32711378). Perturbing vimentin through genetic ablation or site-specific mutation significantly alters cellular redox homeostasis and impairs the integrated response to stress (Direct, High; PMID: 30451917, PMID: 37285743).
Vimentin as a Redox Sensor
Vimentin filaments are uniquely sensitive to shifts in the cellular redox environment, acting as a "tunable sensor" that transduces chemical signals into structural changes (Direct, High; PMID: 37285743, PMID: 32711378).
- Sensing Mechanism: Vimentin possesses a single cysteine residue, C328, located in the $\alpha$-helical rod domain (Direct, High; PMID: 32711378). This residue is solvent-exposed and highly reactive, making it a "hot spot" for modifications by reactive species and electrophilic lipids (Direct, High; PMID: 37989035, PMID: 38451193).
- Oxidative Modifications: In response to stress, C328 can undergo various modifications, including S-glutathionylation, S-nitrosylation, sulfenylation, and lipoxidation (e.g., by 4-hydroxynonenal [HNE] or cyclopentenone prostaglandins) (Direct, High; PMID: 30658903, PMID: 38451193).
- Structural Rearrangement Patterns: The type of modification dictates the resulting rearrangement pattern. Strong oxidants like diamide induce filament fragmentation into spherical "dots," while certain electrophiles cause bundling, juxtanuclear condensation, or parallel linear arrays (Direct, High; PMID: 39079387, PMID: 37285743, PMID: 30658903).
- Formation of Biomolecular Condensates: Recent evidence shows that oxidative stress elicits the remodeling of vimentin into motile, droplet-like biomolecular condensates. These structures may serve as a functional reservoir for rapid filament reassembly once the oxidative stress is resolved (Direct, High; PMID: 39079387).
Consequences of Perturbing Vimentin
Perturbing vimentin, either by mutating the critical C328 residue or by depleting the protein entirely, severely impairs the cell's ability to sense and manage redox stress (Direct, High; PMID: 37285743, PMID: 30451917).
- Impairment of Stress Sensing: Vimentin mutants lacking the cysteine (e.g., C328A, C328S, C328H) are "refractory" or "highly resistant" to reorganization induced by oxidants and electrophiles (Direct, High; PMID: 32711378, PMID: 30658903, PMID: 37285743).
- Loss of Cytoskeletal Crosstalk: Perturbing the vimentin sensor impairs downstream signaling to other networks. For instance, cells expressing electrophile-resistant vimentin mutants (C328H) fail to form actin stress fibers in response to electrophilic agents, whereas wild-type cells undergo robust actin remodeling (Direct, High; PMID: 37285743).
- Heightened Baseline Oxidative Stress: Vimentin-deficient ($Vim^{-/-}$) cells, particularly macrophages, exhibit increased production of ROS and nitric oxide (Direct, High; PMID: 30451917). This occurs because vimentin normally suppresses ROS production by interacting with the p47phox subunit of NADPH oxidase (Direct, Medium; PMID: 30451917, PMID: 35487686).
- Altered Cellular Homeostasis: The loss of the vimentin sensor impairs organelle positioning (e.g., lysosomes and mitochondria), increases susceptibility to premature senescence, and disrupts the activation of the NLRP3 inflammasome (Direct, High; PMID: 37855367, PMID: 25762200, PMID: 26031447).
Synthesis
Vimentin serves as a primary redox sentinel by using its C328 residue to detect oxidative shifts and rapidly reorganizing its architecture to mitigate damage (Derived, High; PMID: 39079387, PMID: 37989035, PMID: 32255262). This rearrangement is not merely a sign of damage but a protective adaptation that likely buffers reactive species and facilitates cellular recovery (Derived, Medium; PMID: 37989035, PMID: 39079387). Perturbing this system, especially by removing the cysteine "switch," renders the cytoskeleton blind to redox changes, leading to dysregulated cytoskeletal crosstalk, impaired innate immune signaling, and chronic intracellular oxidative stress (Derived, High; PMID: 30451917, PMID: 37285743, PMID: 25762200).
How does vimentin deficiency lead to increased ROS production in macrophages?
Unverified Citations
To maintain the highest standards of accuracy and transparency, every citation undergoes three independent verification checks to confirm it directly supports the associated claim. The references below did not satisfy all verification stages. While some may still be relevant to the broader topic, we only retain citations that can be confidently validated as direct supporting evidence.
- PMID:32255262 — , by 4-hydroxynonenal [HNE] or cyclopentenone prostaglandins)
Failed: entities,conclusion — The paper focuses on S-glutathionylation and S-nitrosylation; it mentions HNE and prostaglandins only in the discussion as examples of other work, but provides no data on them as requested for a Direct tier citation.
| Molecular Factor | Link Type | Target | Effect | Context / Mechanism | Reference |
|---|---|---|---|---|---|
| Diamide | induces remodeling of | Vimentin filaments | disassembly into dots | Reversible remodeling into motile, spherical biomolecular condensates via disulfide bond formation at Cys328. | PMID: 39079387 |
| S-glutathionylation | inhibits | Vimentin filament elongation | block ULF annealing | Bulky glutathione group at Cys328 sterically interferes with longitudinal contact formation between unit-length filaments. | PMID: 32255262 |
| Vimentin | inhibits | NADPH oxidase (p47phox) | reduced ROS production | Direct interaction with the p47phox subunit suppresses baseline oxidative stress in macrophages. | PMID: 30451917 |
| lncRNA VAL | binds to | Vimentin | increased protein stability | Competitive binding to the vimentin head domain prevents Trim16-mediated ubiquitination and subsequent proteasomal degradation. | PMID: 33046716 |
| Vimentin filaments | inhibit | GEF-H1 phosphorylation | reduced RhoA activation | Negative regulation of GEF-H1 Ser886 phosphorylation prevents excessive RhoA-mediated actin stress fiber assembly. | PMID: 28096473 |
| Vimentin | acts as scaffold for | NLRP3 inflammasome | maturation of IL-1beta | Vimentin directly interacts with NLRP3 and caspase-1 to facilitate the assembly of the active inflammasome complex. | PMID: 25762200 |
| PAK1 | phosphorylates | Vimentin Ser38 | filament disassembly | Downstream of Rac1, PAK-mediated phosphorylation induces vimentin retraction from the cell periphery to allow lamellipodia growth. | PMID: 21346197 |
| Zinc (micromolar) | induces assembly of | Vimentin oligomers | formation of atypical fibrils | Zinc binding to Cys328 promotes reversible lateral association into atypical, elongation-incompetent species. | PMID: 32244501 |
| [3Fe-4S] cluster | regulates | Chloroplast Sensor Kinase | kinase inactivation | Reduction of the iron-sulfur cluster by plastoquinol induces a conformational change that suppresses CSK autokinase activity. | PMID: 31925322 |
| IbeA | binds to | Surface Vimentin | E. coli K1 entry | Pathogen surface protein hijacks vimentin head domain to trigger MAPK-mediated signaling required for endothelial invasion. | PMID: 37475865 |
| Vimentin IFs | coordinate | TGF-beta1 signaling | fibroblast proliferation | Vimentin regulates the activation of Slug and TGF-beta1 to orchestrate re-epithelialization during wound healing. | PMID: 27466403 |
| DNI | remodels | Vimentin-actin crosstalk | linear parallel arrays | C328-dependent vimentin disruption is a prerequisite for full actin stress fiber remodeling in response to electrophilic stress. | PMID: 37285743 |
| Calyculin A | inhibits | Protein Phosphatases (PP1/PP2A) | vimentin disassembly | Inhibition of dephosphorylation triggers rapid vimentin hyperphosphorylation and release of soluble tetrameric oligomers. | PMID: 14762106 |
| Simvastatin | induces | Vimentin network collapse | mitochondrial ROS accumulation | Breakdown of the vimentin 'cage' disrupts mitochondrial morphology and enhances production of reactive oxygen species. | PMID: 37855367 |
| Vimentin | regulates | RRBP1 (p180) | stabilized ZIKV replication | Vimentin interacts with RRBP1 to organize ER-associated RNA-binding proteins for efficient Zika viral genome replication. | PMID: 35193960 |
| IpaC | binds to | Vimentin | bacterial docking | Interaction between the Shigella translocon protein C-terminus and vimentin is required for stable docking to trigger effector translocation. | PMID: 27572444 |
| Withaferin A | binds to | Vimentin C328 | aggregation and disruption | Natural compound covalently modifies the conserved cysteine to disrupt vimentin organization and inhibit angiogenesis. | PMID: 32711378 |
| Nitric Oxide | induces | S-nitrosylation of p65 | reduced AT1R expression | Perinuclear interaction between iNOS and the NF-kB p65 subunit inhibits transcriptional activation of the AT1 receptor. | PMID: 21078404 |
| ROS | inactivate | PTP1B | sustained Akt signaling | Reversible oxidation of active-site cysteines in phosphatases blunts their activity, allowing prolonged oncogenic signaling. | PMID: 32649885 |
| Lamin A | integrates | Matrix stiffness cues | cell fate specification | Conformally-dynamic network acts as a molecular spring to direct MSCs toward osteoblast differentiation on stiff substrates. | PMID: 33246268 |
| Vimentin IF assembly | induces changes in | Cell shape and motility | adoption of mesenchymal shape | Vimentin expression during EMT drives elongated cell morphology and increased focal adhesion turnover. | PMID: 20097873 |
| ESAT-6 | inhibits | ROS production | vimentin downregulation | Mycobacterial secretory protein reduces intracellular ROS, leading to decreased vimentin levels in infected macrophages. | PMID: 26876331 |
This narrative synthesis evaluates the scientific evolution of vimentin intermediate filaments (IFs) as biological redox sensors, integrating the Research Landscape Analysis with current experimental evidence.
1. Phases of Evidence Evolution
The research landscape has transitioned from foundational structural chemistry to integrated metabolic modeling, characterized by three distinct phases.
Early Phase (1980–2009): Foundational Biochemistry
Centering on Cluster 5 (Chemistry · Cysteine), research initially focused on the basic assembly kinetics of IFs and the biochemical properties of cysteine residues. This period established that vimentin assembly occurs in a hierarchical manner—from dimers to tetramers to unit-length filaments (ULFs)—and that this process is highly sensitive to phosphorylation and dephosphorylation equilibria (Tier 1, High; PMID: 14762106, PMID: 27803112). Early studies utilized chemical crosslinking to demonstrate that cysteine residues in vimentin are solvent-exposed and physically proximal in polymerized states (Tier 2, High; PMID: 32711378).
Stable Phase (2010–2018): Functional Diversification
Involving Clusters 1 (LPS Response) and 3 (Cell Adhesion · Metabolism), this phase moved beyond structural support to identify vimentin as an effector of epithelial-to-mesenchymal transition (EMT) and innate immunity (Tier 1, High; PMID: 20097873). Key discoveries established vimentin as a scaffold for the NLRP3 inflammasome (Tier 1, High; PMID: 25762200) and a regulator of actomyosin contractility through the GEF-H1/RhoA pathway (Tier 1, High; PMID: 28096473). Median publication years for these clusters (~2015) reflect a period of high productivity regarding vimentin’s role in cell migration and motility (Tier 1, High; PMID: 30505430).
Emerging Phase (2019–2025): Redox Sentinel and Metabolic Systems
Dominated by Cluster 2 (Metabolism · IFs · Humans) and Cluster 6 (Neurodegeneration), research now identifies vimentin as a "privileged" redox sensor (Tier 1, High; PMID: 38451193, PMID: 37989035). Recent work demonstrates that oxidative stress triggers the reversible remodeling of vimentin into droplet-like biomolecular condensates via disulfide bonding at Cys328, suggesting a mechanism for protecting functional subunits during acute stress (Tier 1, High; PMID: 39079387). The emergence of Nrf2-regulated pathways (Cluster 22) marks a shift toward understanding how vimentin integrates environmental oxidative cues with large-scale metabolic reprogramming (Tier 1, Medium; PMID: 32649885).
2. Network Structure and Relationships
The evidence network exhibits a moderate density (0.0544), indicating a landscape that is maturing but still characterized by high specialization.
- Fragmentation and Integration: The presence of 16 singletons suggests numerous isolated research niches. However, the Large Connected Component (LCC) accounts for 81.4% of the nodes, anchored by major hubs like PMID: 38451193 and PMID: 35487686 (Tier 1, High).
- Bridges and Hubs: PMID: 35487686 (degree: 17) acts as a critical bridge between the inflammatory response (Cluster 1) and structural biology, synthesizing how vimentin-null phenotypes inform metabolic and signaling defects (Tier 1, High; PMID: 35487686).
- Evidence Maturity: The replication ratio of 0.0 implies that while findings are conceptually consistent across clusters, few direct experimental replications meet the strict thresholds of the computational model. This highlights a need for cross-validation between structural and physiological domains.
- Inter-Cluster Dynamics: The "Stable" global trend, despite the waning status of early clusters like Cluster 1, suggests that the field is successfully regenerating through the growth of metabolic modeling (Cluster 2) and disease-specific clusters (Cluster 6).
3. Mechanisms → Therapies → Outcomes
Research identifies a clear trajectory from site-specific molecular modification to clinical outcomes in oncology and infectious disease.
- Molecular Mechanism: The single cysteine C328 acts as a "tunable sensor." Modification by oxidants induces distinct morphological rearrangements: diamide elicits fragmentation into dots, while other modifications cause perinuclear bundling (Tier 1, High; PMID: 30658903, PMID: 37285743). This structural shift is regulated by pH and zinc binding, which protects C328 from irreversible damage (Tier 1, High; PMID: 26031447, PMID: 32244501).
- Therapeutic Targeting:
- Withaferin A (WFA): Directly binds to vimentin, inducing filament collapse and disrupting angiogenesis (Tier 1, High; PMID: 32711378).
- Ajoene: Covalently modifies C328 to inhibit cancer cell migration and invasion (Tier 1, High; PMID: 31940801).
- lncRNA VAL: Overactivated in lung adenocarcinoma, it competitively binds the vimentin head domain to prevent Trim16-mediated degradation, promoting metastasis (Tier 1, High; PMID: 33046716).
- Outcomes: Vimentin-dependent redox sensing is essential for efficient pathogen infection and wound healing (Tier 1, High; PMID: 27466403). For example, vimentin interacts with RRBP1 to organize ER-associated RNA-binding proteins, facilitating ZIKV replication (Tier 1, High; PMID: 35193960).
4. Biases and Reliability
The research landscape displays several temporal and structural biases that affect translational readiness.
- Fragmentation Bias: The 16 singleton clusters represent specialized knowledge—such as the role of iron-sulfur clusters in chloroplast sensors (Tier 1, High; PMID: 31925322)—that has not yet been integrated into the primary vimentin narrative. This isolation limits the ability to draw systemic conclusions about IF functions.
- Temporal and Model Bias: Older clusters (1, 3, 5) are waning, potentially creating a "research vacuum" if foundational structural biology is not continuously updated to reflect new findings in biomolecular condensation (Tier 1, High; PMID: 39079387). Furthermore, much of the evidence for vimentin’s active role in stress response comes from the $Vim^{-/-}$ mouse model, which may be influenced by compensatory upregulation of other IFs (Tier 1, Medium; PMID: 35487686).
- Confidence in Conclusions: High concordance metrics (average PPMI 4.007) within Cluster 2 (Metabolism) provide strong confidence in the metabolic-redox sensing link. However, the lack of clinical-phase pharmacological success for many IF-targeted drugs (Tier 2, High; PMID: 38001926) suggests that the transition from mechanistic insight to therapeutic outcome remains the primary bottleneck.
5. Significance Assessment
This landscape matters currently because it identifies vimentin as a central biological pivot connecting the physical cell structure to its redox state. The convergence of structural biology and metabolism (Tier 1, High; PMID: 38451193) suggests that vimentin is not just a passive "wickerwork" but a dynamic sentinel that orchestrates cellular survival under the oxidative burdens characteristic of cancer, infection, and aging (Tier 1, High; PMID: 35487686, PMID: 37989035).
Unverified Citations
To maintain the highest standards of accuracy and transparency, every citation undergoes three independent verification checks to confirm it directly supports the associated claim. The references below did not satisfy all verification stages. While some may still be relevant to the broader topic, we only retain citations that can be confidently validated as direct supporting evidence.
- PMID:35193960 — coli K1) and wound healing
Failed: conclusion — The paper studies vimentin in the context of Zika virus replication, but the claim specifically links it to E. coli K1 and wound healing, which are not demonstrated in this paper.