alpha6beta4

alpha6beta4 refers to a specific integrin heterodimer, designated as integrin $\alpha_6\beta_4$. Integrins are a large family of transmembrane cell surface receptors that mediate cell-cell and cell-extracellular matrix adhesion. The alpha6beta4 integrin is composed of two subunits, the alpha-6 (ITGA6) and beta-4 (ITGB4) protein chains.

This particular integrin is primarily found on epithelial cells, where it plays a crucial role in cell adhesion and the maintenance of epithelial structure. It is a key component of hemidesmosomes, which are specialized adhesive structures that connect the basal surface of epithelial cells to the underlying basement membrane. The beta-4 subunit is unique among integrin beta subunits in that it possesses a large intracellular domain that associates with other proteins, including the plectin-intermediate filament network.

The expression of integrin $\alpha_6\beta_4$ is particularly important during development and in tissue homeostasis. Dysregulation of its function or expression has been implicated in various pathological conditions, including certain cancers. In many epithelial cancers, integrin $\alpha_6\beta_4$ is often overexpressed and can contribute to tumor progression, invasion, and metastasis by altering cell adhesion and signaling pathways. Its role in cancer makes it a target of interest for therapeutic interventions.