Mapping the Molecular and Structural Specialization of the Skin Basement Membrane for Inter-Tissue Interactions

The study investigated the role of the basement membrane (BM) in inter-tissue interactions, focusing on mouse hair follicles. Researchers used quantitative transcriptomics and immunohistochemistry to determine the cellular origin, molecular identity, and distribution of extracellular matrix molecules. They discovered that the BM's composition and architecture are highly specialized for different types of interactions, such as those between the epidermis and fibroblasts, muscles, and nerves. Specifically, the study found an asymmetric organization of the BM at the hair germ–dermal papilla interface, with side-specific heterogeneity characterized by distinct interface, hook, and mesh BMs. Laminin α5, a component of these BMs, was identified as essential for the structural and functional integrity of the hair germ–dermal papilla interactions. This research underscores the importance of BM heterogeneity in facilitating various inter-tissue interactions.