Enables thyroid-stimulating hormone receptor activity. Involved in positive regulation of cell population proliferation. Located in membrane raft. Human ortholog(s) of this gene implicated in Graves' disease; cardiomyopathy; congenital nongoitrous hypothyroidism 1; and mitral valve prolapse. Orthologous to human TSHR (thyroid stimulating hormone receptor). [provided by Alliance of Genome Resources, Apr 2022]