Enables small GTPase binding activity. Acts upstream of or within several processes, including intracellular signal transduction; positive regulation of macromolecule metabolic process; and positive regulation of mammary gland epithelial cell proliferation. Located in cell-cell junction; cytoplasm; and lateral plasma membrane. Orthologous to human IQGAP3 (IQ motif containing GTPase activating protein 3). [provided by Alliance of Genome Resources, Apr 2022]