TcdB of <i>Clostridioides difficile</i> Mediates RAS-Dependent Necrosis in Epithelial Cells
A <i>Clostridioides difficile</i> infection (CDI) is the most common nosocomial infection worldwide. The main virulence factors of pathogenic <i>C. difficile</i> are TcdA and TcdB, which inhibit small Rho-GTPases. The inhibition of small Rho-GTPases leads to the so-called cyt...
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MDPI AG
2022-04-01
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| Series: | International Journal of Molecular Sciences |
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| Online Access: | https://www.mdpi.com/1422-0067/23/8/4258 |
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| author | Florian Stieglitz Ralf Gerhard Rabea Hönig Klaudia Giehl Andreas Pich |
| author_facet | Florian Stieglitz Ralf Gerhard Rabea Hönig Klaudia Giehl Andreas Pich |
| author_sort | Florian Stieglitz |
| collection | DOAJ |
| description | A <i>Clostridioides difficile</i> infection (CDI) is the most common nosocomial infection worldwide. The main virulence factors of pathogenic <i>C. difficile</i> are TcdA and TcdB, which inhibit small Rho-GTPases. The inhibition of small Rho-GTPases leads to the so-called cytopathic effect, a reorganization of the actin cytoskeleton, an impairment of the colon epithelium barrier function and inflammation. Additionally, TcdB induces a necrotic cell death termed pyknosis in vitro independently from its glucosyltransferases, which are characterized by chromatin condensation and ROS production. To understand the underlying mechanism of this pyknotic effect, we conducted a large-scale phosphoproteomic study. We included the analysis of alterations in the phosphoproteome after treatment with TcdA, which was investigated for the first time. TcdA exhibited no glucosyltransferase-independent necrotic effect and was, thus, a good control to elucidate the underlying mechanism of the glucosyltransferase-independent effect of TcdB. We found RAS to be a central upstream regulator of the glucosyltransferase-independent effect of TcdB. The inhibition of RAS led to a 68% reduction in necrosis. Further analysis revealed apolipoprotein C-III (APOC3) as a possible crucial factor of CDI-induced inflammation in vivo. |
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| issn | 1661-6596 1422-0067 |
| language | English |
| last_indexed | 2024-03-09T10:34:22Z |
| publishDate | 2022-04-01 |
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| spelling | doaj.art-96544ddb64cf4a32a727f3aa5c8fb0992023-12-01T21:03:28ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672022-04-01238425810.3390/ijms23084258TcdB of <i>Clostridioides difficile</i> Mediates RAS-Dependent Necrosis in Epithelial CellsFlorian Stieglitz0Ralf Gerhard1Rabea Hönig2Klaudia Giehl3Andreas Pich4Institute of Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, GermanyInstitute of Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, GermanySignal Transduction of Cellular Motility, Internal Medicine V, Justus Liebig University Giessen, Aulweg 128, 35392 Giessen, GermanySignal Transduction of Cellular Motility, Internal Medicine V, Justus Liebig University Giessen, Aulweg 128, 35392 Giessen, GermanyInstitute of Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, GermanyA <i>Clostridioides difficile</i> infection (CDI) is the most common nosocomial infection worldwide. The main virulence factors of pathogenic <i>C. difficile</i> are TcdA and TcdB, which inhibit small Rho-GTPases. The inhibition of small Rho-GTPases leads to the so-called cytopathic effect, a reorganization of the actin cytoskeleton, an impairment of the colon epithelium barrier function and inflammation. Additionally, TcdB induces a necrotic cell death termed pyknosis in vitro independently from its glucosyltransferases, which are characterized by chromatin condensation and ROS production. To understand the underlying mechanism of this pyknotic effect, we conducted a large-scale phosphoproteomic study. We included the analysis of alterations in the phosphoproteome after treatment with TcdA, which was investigated for the first time. TcdA exhibited no glucosyltransferase-independent necrotic effect and was, thus, a good control to elucidate the underlying mechanism of the glucosyltransferase-independent effect of TcdB. We found RAS to be a central upstream regulator of the glucosyltransferase-independent effect of TcdB. The inhibition of RAS led to a 68% reduction in necrosis. Further analysis revealed apolipoprotein C-III (APOC3) as a possible crucial factor of CDI-induced inflammation in vivo.https://www.mdpi.com/1422-0067/23/8/4258<i>Clostridioides difficile</i><i>C. diff.</i>TcdBphosphoproteomicsRASTcdA |
| spellingShingle | Florian Stieglitz Ralf Gerhard Rabea Hönig Klaudia Giehl Andreas Pich TcdB of <i>Clostridioides difficile</i> Mediates RAS-Dependent Necrosis in Epithelial Cells International Journal of Molecular Sciences <i>Clostridioides difficile</i> <i>C. diff.</i> TcdB phosphoproteomics RAS TcdA |
| title | TcdB of <i>Clostridioides difficile</i> Mediates RAS-Dependent Necrosis in Epithelial Cells |
| title_full | TcdB of <i>Clostridioides difficile</i> Mediates RAS-Dependent Necrosis in Epithelial Cells |
| title_fullStr | TcdB of <i>Clostridioides difficile</i> Mediates RAS-Dependent Necrosis in Epithelial Cells |
| title_full_unstemmed | TcdB of <i>Clostridioides difficile</i> Mediates RAS-Dependent Necrosis in Epithelial Cells |
| title_short | TcdB of <i>Clostridioides difficile</i> Mediates RAS-Dependent Necrosis in Epithelial Cells |
| title_sort | tcdb of i clostridioides difficile i mediates ras dependent necrosis in epithelial cells |
| topic | <i>Clostridioides difficile</i> <i>C. diff.</i> TcdB phosphoproteomics RAS TcdA |
| url | https://www.mdpi.com/1422-0067/23/8/4258 |
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