Enables G-protein alpha-subunit binding activity. Involved in regulation of G protein-coupled receptor signaling pathway. Predicted to be located in Golgi apparatus; nucleoplasm; and plasma membrane. Predicted to be part of protein-containing complex. Predicted to colocalize with Golgi membrane; cell cortex; and endoplasmic reticulum membrane. Orthologous to human GPSM1 (G protein signaling modulator 1). [provided by Alliance of Genome Resources, Apr 2022]