The study reveals the regulatory mechanism of DNA methylation formed by addictive behavior.

It is one of the characteristics of drug abuse and addiction that addictive drugs strengthen behavioral response. In the process of acquiring the operant conditioned reflex, the relationship between environment / cue and drug reward effect is an important reason for environment / cue to induce relapse after long-term withdrawal.previous studies focused on the role of receptors or protein kinases in the formation of addictive behavior, but could not explain the long-term maintenance of this behavior.DNA methylation mainly inhibits the binding of transcription factors through the addition of methyl group to cytosine in the promoter region of the gene, thus inhibiting gene expression for a long time, which may be a key molecular mechanism for the long-term existence of addiction behavior.researchers from suinan research group, Key Laboratory of mental health, Institute of psychology, Chinese Academy of Sciences, proved that a subtype of DNA methyltransferase (Dnmt3a) plays a key role in the acquisition of morphine drug seeking behavior by applying the behavioral paradigm of rats with morphine self-sufficiency.the study found that the protein expression of Dnmt3a (but not DNMT3b) in hippocampal CA1 area (not NAc shell area of nucleus accumbens) was significantly increased after morphine self-sufficiency training for 1 day and 7 days (see Figure 1).the expression of Dnmt3a in CA1 (see Figure 2) can effectively inhibit the acquisition of morphine self-sufficiency behavior.this study suggests that Dnmt3a in hippocampal CA1 plays an important role in the acquisition of morphine self-sufficiency behavior and provides a potential target for the inhibition of opioid addiction.the research is supported by the national key basic research and development program (973 Program), the National Natural Science Foundation of China and the Key Laboratory of mental health of Chinese Academy of Sciences.related research results were published in addition biology.Fig. 1. Increased expression of Dnmt3a in hippocampal CA1 induced by morphine self-sufficiency; 2. Specific knockdown of Dnmt3a expression in CA1 inhibited the acquisition of morphine self-sufficiency.source: Institute of psychology, Chinese Academy of Sciences