Predicted to be an extracellular matrix structural constituent. Acts upstream of or within brown fat cell differentiation. Located in basement membrane. Part of laminin-5 complex. Is expressed in several structures, including alimentary system; brain; genitourinary system; integumental system; and respiratory system. Used to study junctional epidermolysis bullosa Herlitz type and junctional epidermolysis bullosa non-Herlitz type. Human ortholog(s) of this gene implicated in amelogenesis imperfecta type 1A; junctional epidermolysis bullosa; junctional epidermolysis bullosa Herlitz type; junctional epidermolysis bullosa non-Herlitz type; and lung small cell carcinoma. Orthologous to human LAMB3 (laminin subunit beta 3). [provided by Alliance of Genome Resources, Apr 2022]