The gene early growth response protein 1 (EGR1) is an immediate early gene (IEG). EGR1 can rapidly be induced by neuronal activity. The defining characteristic of IEGs is the rapid and transient up-regulation—within minutes—of their mRNA levels independent of protein synthesis. In adulthood, EGR1 is expressed widely throughout the brain, maintaining baseline expression levels in several key areas of the brain including the medial prefrontal cortex, striatum, hippocampus and amygdala. This expression is linked to control of cognition, emotional response, social behavior and sensitivity to reward. EGR1 binds to DNA at sites with the motifs 5′-GCGTGGGCG-3′ and 5'-GCGGGGGCGG-3′ and these motifs occur primarily in promoter regions of genes. The short isoform TET1s is expressed in the brain. EGR1 and TET1s form a complex mediated by the C-terminal regions of both proteins, independently of association with DNA. EGR1 recruits TET1s to genomic regions flanking EGR1 binding sites. In the presence of EGR1, TET1s is capable of locus-specific demethylation and activation of the expression of downstream genes regulated by EGR1.