“…Various mechanisms have been proposed to explain nicotine-mediated up-regulation Buccafusco et al, 2009;Benowitz, 2010;Changeux, 2010b;Mao and McGehee, 2010). One hypothesis is that the initial receptor desensitization contributes to upregulation, possibly via receptor phosphorylation (Léna and Changeux, 1993;Swope et al, 1999;Wiesner and Fuhrer, 2006). More recently, it has been proposed that nicotine acts as a chaperone to promote maturation of ␣4 nAChR subunit precursors that might otherwise be degraded by currently unidentified endogenous molecular components (Sallette et al, 2005;Corringer et al, 2006;Tumkosit et al, 2006;Kuryatov et al, 2008;Walsh et al, 2008;Lester et al, 2009;Jones et al, 2010).…”