Ghrelin? Are you referencing ghrelin? There were fairly recent reports of increasing evidence that peptide systems regulating food consumption, including ghrelin, are also critical players in excessive alcohol consumption. However there are many genes that play a role in the susceptibility to, as well as the effects of, alcoholism. Genes code for proteins. Many genes=many proteins.
Actin and myosin. They make up muscle fibers which bring the drink to mouth.