Enables cargo adaptor activity. Acts upstream of or within several processes, including cell-substrate junction organization; platelet-derived growth factor receptor signaling pathway; and ruffle assembly. Located in cell leading edge; cell projection; and clathrin-coated pit. Is expressed in genitourinary system. Orthologous to several human genes including STON1-GTF2A1L (STON1-GTF2A1L readthrough). [provided by Alliance of Genome Resources, Apr 2022]