Cytoplasmic keratins couple with and maintain nuclear envelope integrity in colonic epithelial cells
Carl-Gustaf A. Stenvall, Joel H. Nyström, Ciarán Butler-Hallissey, Theresia Jansson, Taina R. H. Heikkilä, Stephen A. Adam, Roland Foisner, Robert D. Goldman, Karen M. Ridge, Diana M. Toivola
Abstract
mice following tamoxifen administration significantly decreased lamin levels at day 4 when K8 levels had reduced to 40%. K8 loss also led to reduced levels of plectin, LINC complex, and lamin-associated proteins. While keratins were not seen in the nucleoplasm without or with leptomycin B treatment, keratins were found intimately located at the nuclear envelope and complexed with SUN2 and lamin A. Furthermore, K8 loss in Caco-2 cells compromised nuclear membrane integrity basally and after shear stress. In conclusion, colonocyte K8 helps maintain nuclear envelope and lamina composition and contributes to nuclear integrity.