Enables several functions, including PDZ domain binding activity; myosin II binding activity; and protein N-terminus binding activity. Contributes to gamma-aminobutyric acid transmembrane transporter activity. Involved in gamma-aminobutyric acid import; import across plasma membrane; and positive regulation of ion transmembrane transport. Located in several cellular components, including apical plasma membrane; membrane raft; and microvillus membrane. Part of plasma membrane protein complex. Biomarker of hypertension. Human ortholog(s) of this gene implicated in hypophosphatemic nephrolithiasis/osteoporosis 2. Orthologous to human SLC9A3R1 (SLC9A3 regulator 1). [provided by Alliance of Genome Resources, Apr 2022]