Enables acetylcholine-gated cation-selective channel activity. Involved in negative regulation of ERK1 and ERK2 cascade and sensory perception of sound. Part of acetylcholine-gated channel complex. Is active in cholinergic synapse. Is integral component of postsynaptic specialization membrane. Orthologous to human CHRNA9 (cholinergic receptor nicotinic alpha 9 subunit). [provided by Alliance of Genome Resources, Apr 2022]