Muc4 - mucin 4, cell surface associated

Enables ErbB-2 class receptor binding activity. Involved in several processes, including estrous cycle; negative regulation of T cell mediated cytotoxicity directed against tumor cell target; and negative regulation of cell adhesion. Located in several cellular components, including apical plasma membrane; extracellular space; and microvillus membrane. Part of protein-containing complex. Colocalizes with endoplasmic reticulum. Biomarker of cholangiocarcinoma; corneal neovascularization; mucositis; and otitis media. Human ortholog(s) of this gene implicated in pancreatic cancer. Orthologous to human MUC4 (mucin 4, cell surface associated). [provided by Alliance of Genome Resources, Apr 2022]