The intrinsically disordered, epigenetic factor RYBP binds to the citrullinating enzyme PADI4 in cancer cells

Araujo-Abad, Salomé ; Fuentes-Baile, María ; Rizzuti, Bruno ; Bazán, J. Fernando ; Villamarin-Ortiz, Adrián ; Saceda, Miguel ; Fernández, Eduardo ; Vidal, Miguel ; Abian, Olga (Universidad de Zaragoza) ; Velázquez-Campoy, Adrián (Universidad de Zaragoza) ; Juan Romero, Camino de ; Neira, José L. (Universidad de Zaragoza)

Resumen: RYBP (Ring1 and YY 1 binding protein) is a multifunctional, intrinsically disordered protein (IDP), best described as a transcriptional regulator. It exhibits a ubiquitin-binding functionality, binds to other transcription factors, and has a key role during embryonic development. RYBP, which folds upon binding to DNA, has a Zn-finger domain at its N-terminal region. By contrast, PADI4 is a well-folded protein and it is one the human isoforms of a family of enzymes implicated in the conversion of arginine to citrulline. As both proteins intervene in signaling pathways related to cancer development and are found in the same localizations within the cell, we hypothesized they may interact. We observed their association in the nucleus and cytosol in several cancer cell lines, by using immunofluorescence (IF) and proximity ligation assays (PLAs). Binding also occurred in vitro, as measured by isothermal titration calorimetry (ITC) and fluorescence, with a low micromolar affinity (~1 μM). AlphaFold2-multimer (AF2) results indicate that PADI4's catalytic domain interacts with the Arg53 of RYBP docking into its active site. As RYBP sensitizes cells to PARP (Poly (ADP-ribose) polymerase) inhibitors, we applied them in combination with an enzymatic inhibitor of PADI4 observing a change in cell proliferation, and the hampering of the interaction of both proteins. This study unveils for the first time the possible citrullination of an IDP, and suggests that this new interaction, whether it involves or not citrullination of RYBP, might have implications in cancer development and progression.

Idioma: Inglés

DOI: 10.1016/j.ijbiomac.2023.125632

Año: 2023

Publicado en: International journal of biological macromolecules 246 (2023), 125632 [14 pp.]
ISSN: 0141-8130

Factor impacto JCR: 7.7 (2023)

Categ. JCR: BIOCHEMISTRY & MOLECULAR BIOLOGY rank: 34 / 313 = 0.109 (2023) - Q1 - T1
Categ. JCR: POLYMER SCIENCE rank: 6 / 95 = 0.063 (2023) - Q1 - T1
Categ. JCR: CHEMISTRY, APPLIED rank: 6 / 74 = 0.081 (2023) - Q1 - T1

Factor impacto CITESCORE: 13.7 - Biochemistry (Q1) - Biomaterials (Q1) - Food Science (Q1) - Molecular Biology (Q1) - Structural Biology (Q1)

Factor impacto SCIMAGO: 1.245 - Biochemistry (Q1) - Structural Biology (Q2) - Molecular Biology (Q2)

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/ISCIII/PI22-00824
Financiación: info:eu-repo/grantAgreement/ES/MICINN/AEI/PID2021-127296OB-I00
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PDC2022-133952-I00
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CP19-00095

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Bioquímica y Biolog.Mole. (Dpto. Bioq.Biolog.Mol. Celular)
Área (Departamento): Área Lenguajes y Sistemas Inf. (Dpto. Informát.Ingenie.Sistms.)