Epithelia is of the most abundant tissue types in animals. Epithelial cells are held together through cell-cell junctions such as tight (TJ) and adherens (AJ) junctions. How the molecular architecture of the junctions is adapted to physiological needs and how it is regulated is not entirely clear. First, we characterised the expression, localisation, and interaction of junctional proteins in cultured epithelial cell lines. We showed that every cell type is unique in their morphology, molecular organisation, expression, and distribution of junctional proteins and their interactions. Next, we aimed to uncover new functions of cytoskeleton-associated cytoplasmic proteins at TJ and AJ, cingulin and paracingulin, using CRISPR-KO cell lines. Cingulin regulates junctional accumulation of F-actin, g-actin, nonmuscle myosin 2B and ARHGEF18. It plays role in the regulation of ZO-1 conformation, promotes its association with F-actin and stabilises it at junctions. Cingulin and paracingulin regulate TJ membrane shape and form liquid-like droplets.