Assays for the Calcium Sensitivity of Desmosomes

Abstract

Epithelial cells in vivo exist as confluent cell sheets, but this confluence is disrupted if the sheets are wounded, if the cells are undergoing morphogenesis, or if they are taking part in invasion and metastasis. Desmosomes are one of the principal types of adhesive junctions in epithelia and are responsible for maintaining tissue integrity. It is likely that modulation of desmosomal adhesion is required to facilitate cell motility in response to alterations in the tissue architecture. Desmosomal adhesion changes from a calcium-dependent state to a calcium-independent state when cells become confluent. Our laboratory has shown that the alpha isoform of protein kinase C is involved in signaling the response of desmosomes to calcium concentration and wounding, in cultured epithelial cells and in mouse epidermis (in vivo).

Endoplasmic Reticulum Calcium Regulates Epidermal Barrier Response and Desmosomal Structure

“…Desmosomes are remodeled, signified by changes in the desmosomal adhesive strength and midline structures seen on EM (Garrod and Chidgey, 2008), after processes that change epidermal or keratinocyte Ca 2+ , such as wounding, or Darier and Hailey-Hailey disease (de Dobbeleer and Achten, 1979; Dhitavat et al, 2004; Garrod et al, 2005; Gottlieb and Lutzner, 1970; Hobbs et al, 2011; Merritt et al, 2006). Because we find marked and rapid shifts in ER and cytosolic Ca 2+ after barrier perturbation, we next looked at cell-to-cell adhesion responses to barrier perturbation at the electron microscopy level.…”

Cell autonomous role of iASPP deficiency in causing cardiocutaneous disorders

“…The cells were subsequently subjected to immunocytochemistry protocol with desmoplakin antibody. Calcium chelation protocol has been described before elsewhere [50].…”