Scaffold protein that connects plasma membrane proteins with members of the ezrin/moesin/radixin family and thereby helps to link them to the actin cytoskeleton and to regulate their surface expression. Necessary for cAMP-mediated phosphorylation and inhibition of SLC9A3. May also act as scaffold protein in the nucleus (By similarity). Homodimer, and heterodimer with SLC9A3R1. Binds ADRB2, SLC9A3, P2RY1, P2YR2, SRY, RDX, PDZK1 and LPAR2 (By similarity). Found in a complex with EZR, PODXL and SLC9A3R2 (By similarity). Interacts (via the PDZ domains) with PODXL (via the C-terminal PDZ-binding motif DTHL); interaction is detected in glomerular epithelium cells (By similarity). Binds PODXL. Interacts with SGK1 and KCNJ1/ROMK1 (By similarity). Interacts (via the PDZ domains) with SLC26A6 (By similarity). Localizes with EZR and PODXL at the apical cell membrane of glomerular epithelium cells and the sides of the food processes. Nuclear, in a punctate pattern (By similarity). Detected in kidney glomeruli.