HMG20A plays a role in neuronal differentiation as chromatin-associated protein. HMG20A acts as inhibitor of HMG20B. HMG20A overcomes the repressive effects of the neuronal silencer REST and induces the activation of neuronal-specific genes. HMG20A involved in the recruitment of the histone methyltransferase MLL and consequent increased methylation of histone H3 lysine 4