Biophysical Society Thematic Meeting | Singapore

Mechanobiology of Disease

Poster Abstracts

16-POS Board 16 Energy Landscape of RGD Motif and Syndecan-1 Binding to Human Bladder Cells of

Different Grades Studied by Dynamic Force Spectroscopy Joanna Danilkiewicz , Joanna Pabijan, Malgorzata Lekka. Institute of Nuclear Physics, PAS, Kraków, Lesser, Poland.

Multiple receptors present on cell membrane mediate various interactions with extracellular matrix (ECM). Many processes occurring in metastasis such as cell adhesion, migration, attachment to basal matrix, and invasion involve proteins containing the RGD motif such as fibronectin or vitronectin [1]. Thus, many cellular processes (like cell differentiation, adhesion, migration, proliferation or survival) depend on the ECM properties. The main family of cell surface receptors responsible for the cell–ECM interaction are integrins [2]. They bind to ECM proteins mainly through RGD motif. However, in such proteins as fibronectin, another cell attachment sites i.e. heparin binding sites are present to be specifically recognized by syndecan family acting as integrin co-receptors [3]. In our studies, the unbinding properties were quantified for integrins and syndecans, assuming that they change during the metastasis progression. An AFM-based dynamic force spectroscopy (DFS) was used to carry out measurements of the interactions between the cell surface and the AFM probes functionalized with either the RGD motif or monoclonal antibody against syndecan-1. Human bladder cells originated from non-malignant epithelial cells of ureter (HCV29) and from transitional cell carcinoma (HT1376). Obtained loading rate dependences enabled to re-construct the energy landscapes according to the Bell-Evans model used to characterize the unbinding properties of studied interactions. References: [1] Plow et al. J. Biol.Chem. 275, 21785-21788 (2000). [2] Carey Biochem. J. 327, 1–16 (1997). [3] Harisi et al. Onco Targets Ther.8, 1387-1398 (2015). [4] The studies has been financed by the NCN project no UMO-2014/15/B/ST4/04737.

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