Component of neuronal acetylcholine receptors (nAChRs) that function as pentameric, ligand-gated cation channels with high calcium permeability among other activities. nAChRs are excitatory neurotrasnmitter receptors formed by a collection of nAChR subunits known to mediate synaptic transmission in the nervous system and the neuromuscular junction. Each nAchR subunit confers differential attributes to channel properties, including activation, deactivation and desensitization kinetics, pH sensitivity, cation permeability, and binding to allosteric modulators (PubMed:11118490, PubMed:16835356, PubMed:35889515). Has an accessory rather than functional role and is only able to form functional nAChRs when co-assembled with another beta subunit (PubMed:11118490, PubMed:16835356). Participates in pentameric assemblies along with CHRNA3, CHRNA4, CHRNA6, CHRNB2 and CHRNB4 (PubMed:11118490, PubMed:16835356). Modulates receptor assembly and increases receptor sensitivity to nicotine when associated with CHRNB2, CHRNA4 and/or CHRNA6 as well as CHRNA3 and CHRNB4 (PubMed:11118490, PubMed:16835356). Seems to play a role in nicotine addiction (PubMed:11118490, PubMed:16835356). {ECO:0000269|PubMed:11118490, ECO:0000269|PubMed:16835356, ECO:0000269|PubMed:35889515}. This is the function of CHRNB3 (cholinergic receptor nicotinic beta 3 subunit, ENSG00000147432).