miRNAs are small (~22 nucleotides) non-coding mRNAs that can bind to complementary sequences located in the 3’-untranslated region of target mRNAs and promote degradation of the mRNA or repress its translation, thereby leading to expression silencing [83]. Importantly, each miRNA can control hundreds of mRNAs and each mRNA can be targeted by multiple miRNAs. Moreover, multiple miRNAs can either cooperate or compete for the regulation of common mRNA targets [e.g., 84, 85]. Regulation of miRNA levels by ethanol therefore represents a potential mechanism to coordinate expression levels of ethanol-responsive gene sets. Evidence for miRNA-mediated regulation of gene expression by ethanol was first provided by ex vivo studies. In neurosphere cultures derived from fetal mouse cortex, ethanol was shown to cause up-regulation of Jag1, a notch receptor ligand, through the combined suppression of miR-335, miR-21 and miR-153 [85]. In cultured neurons exposed to ethanol, miR-9 up-regulation altered the relative expression of splice variants of the alpha subunit of the large conductance calcium- and voltage-activated potassium (BK) channel (Kcnma1), thereby favoring the expression of BK isoforms resistant to ethanol-induced potentiation [86]. Systematic
