Vimentin Mediates Uptake of C3 Exoenzyme

Rohrbeck, Astrid; Schröder, Arne; Hagemann, Sandra; Pich, Andreas; Höltje, Markus; Ahnert‐Hilger, Gudrun; Just, Ingo

doi:10.1371/journal.pone.0101071

Cited by 33 publications

(51 citation statements)

References 74 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Western blot analysis again confirmed depletion of vimentin in the synaptosomal fraction compared to the homogenate. The interaction of surface vimentin with clostridial C3 transferase was first shown by our group in neuronal and macrophage cell lines (Rohrbeck et al, 2014(Rohrbeck et al, , 2015. Indeed, incubation of spinal cord synaptosomes for 1 hr at 4 C with 8 and 40 ng/μl of recombinant protein followed by stringent washing resulted in a concentration-dependent binding of vimentin ( Figure 6b).…”

Section: Resultsmentioning

confidence: 66%

See 1 more Smart Citation

Release of astroglial vimentin by extracellular vesicles: Modulation of binding and internalization of C3 transferase in astrocytes and neurons

Adolf

Rohrbeck

Münster-Wandowski

et al. 2018

Glia

Self Cite

View full text Add to dashboard Cite

Clostridium botulinum C3 transferase (C3bot) ADP‐ribosylates rho proteins to change cellular functions in a variety of cell types including astrocytes and neurons. The intermediate filament protein vimentin as well as transmembrane integrins are involved in internalization of C3bot into cells. The exact contribution, however, of these proteins to binding of C3bot to the cell surface and subsequent cellular uptake remains to be unraveled. By comparing primary astrocyte cultures derived from wild‐type with Vim−/− mice, we demonstrate that astrocytes lacking vimentin exhibited a delayed ADP‐ribosylation of rhoA concurrent with a blunted morphological response. This functional impairment was rescued by the extracellular excess of recombinant vimentin. Binding assays using C3bot harboring a mutated integrin‐binding RGD motif (C3bot‐G89I) revealed the involvement of integrins in astrocyte binding of C3bot. Axonotrophic effects of C3bot are vimentin dependent and postulate an underlying mechanism entertaining a molecular cross‐talk between astrocytes and neurons. We present functional evidence for astrocytic release of vimentin by exosomes using an in vitro scratch wound model. Exosomal vimentin+ particles released from wild‐type astrocytes promote the interaction of C3bot with neuronal membranes. This effect vanished when culturing Vim−/− astrocytes. Specificity of these findings was confirmed by recombinant vimentin propagating enhanced binding of C3bot to synaptosomes from rat spinal cord and mouse brain. We hypothesize that vimentin+ exosomes released by reactive astrocytes provide a novel molecular mechanism constituting axonotrophic (neuroprotective) and plasticity augmenting effects of C3bot after spinal cord injury.

show abstract

Section: Resultsmentioning

confidence: 66%

“…and primary neuronal cultures (Adolf et al, 2016;Rohrbeck et al, 2014Rohrbeck et al, , 2017. In subsequent studies, we applied C3bot harboring the mutated major integrin-binding site Arg-Gly-Asp (RGD motif ) and identified the β1-subunit of integrin as an additional interaction partner in neuronal cells, macrophages, and CHO cells (Rohrbeck et al, 2017).…”

mentioning

confidence: 99%

Release of astroglial vimentin by extracellular vesicles: Modulation of binding and internalization of C3 transferase in astrocytes and neurons

Adolf

Rohrbeck

Münster-Wandowski

et al. 2018

Glia

Self Cite

View full text Add to dashboard Cite

show abstract

“…Yet there are substantial gaps in our knowledge about uptake and molecular effects of C3. However, recently, it was clearly shown that intermediate filament protein vimentin is crucial for binding and uptake of C3 into neuronal cells (Rohrbeck et al 2014;Adolf et al 2016). The mechanism how vimentin reaches the cell surface is unknown so far.…”

Section: Resultsmentioning

confidence: 99%

“…To identify the membrane interaction partner of C3, different binding assays with subsequent mass spectrometric analyses of the bound proteins were performed and the intermediate filament vimentin was identified (Rohrbeck et al 2014). It is known that vimentin is not exclusively intracellularly localized, but it is also expressed at the cell surface (Podor et al 2002;Mor-Vaknin et al 2003;Mitra et al 2015).…”

Section: Identification Of Vimentin As Binding Partner Of C3mentioning

confidence: 99%

“…The extracellular addition of recombinant vimentin caused a biphasic effect which is dependent on the vimentin concentration. Low extracellular concentrations of vimentin led to increased binding of C3, whereas high concentrations decreased binding of C3 (Rohrbeck et al 2014). One explanation is that vimentin forms oligomers in the culture medium at high concentrations, which allows binding of C3 to vimentin oligomers.…”

Section: Identification Of Vimentin As Binding Partner Of C3mentioning

confidence: 99%

See 1 more Smart Citation

Cell Entry of C3 Exoenzyme from Clostridium botulinum

Rohrbeck

Just

2016

Current Topics in Microbiology and Immunology

Self Cite

View full text Add to dashboard Cite

Clostridium botulinum C3 is the prototype of C3-like ADP-ribosyltransferases that selectively ADP-ribosylate the small GTP-binding proteins RhoA/B/C and inhibit their downstream signaling pathways. It is used as pharmacological tool to study cellular Rho functions. In addition, C3bot harbors a transferase-independent activity on neurons to promote axonal and dendritic growth and branching. Many bacterial protein toxins interact specifically with proteins and/or other membrane components at the surface of target cells. Binding enables access to the appropriate cellular compartment so that the knowledge of the receptor allows essential insight into the mechanism of these toxins. Unlike other bacterial protein toxins (such as the clostridial C1 and C2 toxins from C. botulinum), C3 exoenzyme is devoid of a binding and translocation domain, with which toxins usually initiate receptor-mediated endocytosis followed by access to the intact cell. To date, no specific mechanism for internalization of C3 exoenzyme has been identified. Recently, vimentin was identified as membranous C3-binding partner involved in binding and uptake of C3. Although vimentin is not detected in neurons, vimentin is re-expressed after damage in regenerating neurons. Reappearance of vimentin allows C3 to get access to lesioned neurons/axons to exhibit axonotrophic and dentritotrophic effects.

show abstract

Role of Wasp and the small GTPases RhoA, RhoB, and Cdc42 during capacitation and acrosome reaction in spermatozoa of English guinea pigs

Delgado-Buenrostro

Mújica

Chiquete-Félix

et al. 2016

Molecular Reproduction Devel

View full text Add to dashboard Cite

Cytoskeleton remodeling is necessary for capacitation and the acrosome reaction in spermatozoa. F-actin is located in the acrosome and equatorial region during capacitation, but is relocated in the post-acrosomal region during the acrosome reaction in spermatozoa from bull, rat, mice, and guinea pig. Actin polymerization and relocalization are generally regulated by small GTPases that activate Wasp protein, which coordinates with Arp2/3, profilin I, and profilin II to complete cytoskeletal remodeling. This sequence of events is not completely described in spermatozoa, though. Therefore, the aim of this study was to determine if Wasp interacts with small GTPases (RhoA, RhoB, and Cdc42) and proteins (Arp2/3, profilin I, and profilin II) that co-localize with F-actin during capacitation and the acrosome reaction in English guinea pig spermatozoa obtained from the vas deferens. The spermatozoa were capacitated in calcium-free medium, incubated with an activator or an inhibitor of GTPases, and then induced to acrosome react using calcium. The distribution patterns of F-actin were compared to the patterns of Wasp and its putative interaction partners: Wasp and RhoB, but not RhoA or Cdc42, localization overlap with F-actin during capacitation and the acrosome reaction. Activation of small GTPases localized RhoB to the post-acrosomal region whereas their inhibition prevented acrosome exocytosis. Arp2/3 and profilin II appear to interact with Wasp in the post-acrosomal region and flagellum, while profilin I and Wasp could be found in the equatorial region. Thus, Wasp and F-actin distribution overlap during capacitation and acrosome reaction, and small GTPases play an important role in cytoskeleton remodeling during these processes in spermatozoa. Mol. Reprod. Dev. 83: 927-937, 2016 © 2016 Wiley Periodicals, Inc.

show abstract

Vimentin Mediates Uptake of C3 Exoenzyme

Cited by 33 publications

References 74 publications

Release of astroglial vimentin by extracellular vesicles: Modulation of binding and internalization of C3 transferase in astrocytes and neurons

Release of astroglial vimentin by extracellular vesicles: Modulation of binding and internalization of C3 transferase in astrocytes and neurons

Cell Entry of C3 Exoenzyme from Clostridium botulinum

Role of Wasp and the small GTPases RhoA, RhoB, and Cdc42 during capacitation and acrosome reaction in spermatozoa of English guinea pigs

Contact Info

Product

Resources

About