Pan-claudin family interactome analysis reveals shared and specific interactions

Interactome study of the pan-claudin family by combining two complementary pull-down techniques followed by mass spectrometry to create an interaction landscape of the claudin family. Co-immunoprecipitation (CoIP) of recombinant claudins expressed in MDCK-C7 cells provided information about interactions beyond the already known TJ proteins. A protein interaction screen on a peptide matrix (PRISMA) allowed mapping interactions along the disordered cytosolic C-terminal region of claudins and studying the effect of post-translational modifications (PTMs) on these interactions. The new interaction partners of the C-terminus of several claudins were confirmed by proximity ligation assays (PLA) and revealed their possible implications in localized biological processes in epithelial cells. By combining these approaches, we created an extended interaction map of the claudin protein family, expanding the current knowledge in the field.