Identification of the Interacting Domains Between Tissue Factor and β1-Integrin and the Signalling Properties of the Two Fibronectin-like Domains of Tissue Factor

Featherby, Sophie J.; Faulkner, Eamon C.; Maraveyas, Anthony; Ettelaie, Camille

Abstract

Background: Interactions between tissue factor (TF) and β1-integrin induce cell signals, but the molecular mechanisms are not completely understood. The extracellular domain of TF and EGF4-βTD domains of β1-integrin were hypothesised to be the most likely domains involved in the interaction. Additionally, the interaction may induce a conformational change in β1-integrin, which results in changes in signalling. Methods: Peptide constructs corresponding to the upper (residues 1–110; UED), lower (residues 106–219; LED) or combined extracellular domain (residues 1–219; TED) of TF were produced, as well as peptides corresponding to EGF4-βTD or EGF4 domains of β1-integrin. These constructs were expressed in TF-rich MDA-MB-231 cells and TF-deficient primary endothelial cells. The association of the peptides with endogenous-TF or β1-integrin was assessed by a proximity ligation assay and co-immunoprecipitation. Additionally, the influence of the constructs on β1-integrin conformation and the outcome on ERK1/2 activation, cyclin D expression and cell proliferation was analysed. Results: In MDA-MB-231 cells, all TF-constructs were associated with β1-integrin whilst LED was co-immunopurified with β1-integrin. EGF4-βTD was associated with and co-immunopurified with endogenous TF. Additionally, the expression of UED or EGF4-βTD reduced ERK phosphorylation and cyclin D expression and suppressed proliferation. In endothelial cells, the expression of UED, and to a lesser extent, LED, reduced the proportion of β1-integrin in the active conformation and induced ERK1/2 phosphorylation but did not induce cyclin D expression or proliferation. Conclusions: Collectively, these data indicate the extracellular domains of TF function together, with the lower domain forming a robust interaction with the βTD of β1-integrin and the upper domain inducing cell signalling by regulating β1-integrin conformation.

Citation

Featherby, S. J., Faulkner, E. C., Maraveyas, A., & Ettelaie, C. (2025). Identification of the Interacting Domains Between Tissue Factor and β1-Integrin and the Signalling Properties of the Two Fibronectin-like Domains of Tissue Factor. Cancers, 17(4), Article 644. https://doi.org/10.3390/cancers17040644

• Journal Article Type: Article
• Acceptance Date: Feb 7, 2025
• Online Publication Date: Feb 14, 2025
• Publication Date: Feb 2, 2025
• Deposit Date: Mar 23, 2025
• Publicly Available Date: Mar 24, 2025
• Journal: Cancers
• Electronic ISSN: 2072-6694
• Publisher: MDPI
• Peer Reviewed: Peer Reviewed
• Volume: 17
• Issue: 4
• Article Number: 644
• DOI: https://doi.org/10.3390/cancers17040644
• Keywords: Tissue factor; β1-integrin; Fibronectin-like domains; EGF4 domain; βTD domain; Cell signalling; Cell proliferation
• Public URL: https://hull-repository.worktribe.com/output/5083369