Immunoelectron microscopic localization of a fibronectin-like molecule in Dugesia lugubris s.l

Fibronectin (FN)-like protein has been localized by immunoelectron microscopy in the extracellular matrix (ECM) of planaria Dugesia lugubris s.l. The immunolabeling was present in both intercellular spaces of epidermal cells and the basement membrane, however the amount and distribution of gold particles seemed to be substantially different. FN-like material increased markedly during the passage of migrating cells through the basement membrane from the parenchyma to the epidermis. Gold particles were often found at cell-matrix contacts. Our result suggest that FN-like molecules detected in planarian ECM may be involved not only in cell adhesion but also in promoting cell migration and in regulating the epidermal cell turnover.