Type I cadherins are a class of proteins that play a crucial role in cell adhesion, helping cells stick together to form tissues. They are characterized by their single transmembrane domain and a series of extracellular cadherin repeats, which facilitate homophilic binding—meaning they bind to the same type of cadherin on adjacent cells. This interaction is essential for maintaining the structural integrity of tissues. These proteins are involved in various biological processes, including embryonic development, tissue formation, and cell signaling. Type I cadherins, such as E-cadherin, are particularly important in epithelial tissues, where they help regulate cell behavior and maintain tissue architecture.