Transcription factor 4 (TCF4), also known as SEF2, ITF2, E2-2, and ME2, binds to the immunoglobulin enchancer Mu-E5/KE5-motif. Involved in the initiation of neuronal differentiation. Activates transcription by binding to the E box (5'-CANNTG-3'). Binds to the E-box present in the somatostatin receptor 2 initiator element (SSTR2-INR) to activate transcription By similarity. Human TCF4 mRNA expression is particularly high in the brain.