Unveiling the Binding between the Armadillo-Repeat Domain of Plakophilin 1 and the Intrinsically Disordered Transcriptional Repressor RYBP

Araujo-Abad, Salome ; Rizzuti, Bruno ; Vidal, Miguel ; Abian, Olga (Universidad de Zaragoza) ; Fárez-Vidal, María Esther ; Velázquez-Campoy, Adrián (Universidad de Zaragoza) ; De Juan Romero, Camino ; Neira, José L.

Resumen: Plakophilin 1 (PKP1), a member of the p120ctn subfamily of the armadillo (ARM)-repeat-containing proteins, is an important structural component of cell–cell adhesion scaffolds although it can also be ubiquitously found in the cytoplasm and the nucleus. RYBP (RING 1A and YY1 binding protein) is a multifunctional intrinsically disordered protein (IDP) best described as a transcriptional regulator. Both proteins are involved in the development and metastasis of several types of tumors. We studied the binding of the armadillo domain of PKP1 (ARM-PKP1) with RYBP by using in cellulo methods, namely immunofluorescence (IF) and proximity ligation assay (PLA), and in vitro biophysical techniques, namely fluorescence, far-ultraviolet (far-UV) circular dichroism (CD), and isothermal titration calorimetry (ITC). We also characterized the binding of the two proteins by using in silico experiments. Our results showed that there was binding in tumor and non-tumoral cell lines. Binding in vitro between the two proteins was also monitored and found to occur with a dissociation constant in the low micromolar range (~10 μM). Finally, in silico experiments provided additional information on the possible structure of the binding complex, especially on the binding ARM-PKP1 hot-spot. Our findings suggest that RYBP might be a rescuer of the high expression of PKP1 in tumors, where it could decrease the epithelial–mesenchymal transition in some cancer cells.

Idioma: Inglés

DOI: 10.3390/biom14050561

Año: 2024

Publicado en: Biomolecules 14, 5 (2024), 561 [17 pp.]
ISSN: 2218-273X

Financiación: info:eu-repo/grantAgreement/ES/DGA/B25-20R
Financiación: info:eu-repo/grantAgreement/ES/DGA/E45-20R
Financiación: info:eu-repo/grantAgreement/ES/ISCIII-ERDF-ESF/PI21-00394
Financiación: info:eu-repo/grantAgreement/ES/MICINN/AEI/PID2021-127296OB-I00

Tipo y forma: Article (Published version)

Área (Departamento): Área Bioquímica y Biolog.Mole. (Dpto. Bioq.Biolog.Mol. Celular)