Enables ErbB-3 class receptor binding activity; epidermal growth factor receptor binding activity; and epidermal growth factor-activated receptor activity. Involved in epidermal growth factor receptor signaling pathway; regulation of synapse assembly; and regulation of synapse maturation. Is active in GABA-ergic synapse and glutamatergic synapse. Orthologous to human NRG2 (neuregulin 2). [provided by Alliance of Genome Resources, Apr 2022]