“…These include genes that are important for neuronal plasticity, such as the immediate-early genes Erg1, Creb, and Bdnf, which showed an increase in expression following contextual fear learning, concomitant with the increase in histone acetylation (Bannerman et al, 2014; Korzus et al, 2004; Oliveira et al, 2011). Indeed, all of these molecules have been shown to be critically involved in different stages of the addiction process and the expression of maladaptive reward behaviors (Go et al, 2016; Hoffmann et al, 2017; Li et al, 2016; Rovaris et al, 2017; Sun et al, 2015; Zhang et al, 2016). Relevantly, during this time window, Ca 2+ -induced cAMP signaling that engages the ERK and PKA pathways in the hippocampus and the amygdala directly phosphorylate and thus activate the transcription factor cAMP-response element-binding protein (CREB), a process critical to long-term memory (Dash et al, 1990; Freytag et al, 2017; Serita et al, 2017; Stevens, 1994).…”