This superfamily represents a DNA-binding domain with a 2-layer beta(3)-alpha fold that is found in several DNA-binding proteins, including:DNA-binding domain of tn916 integrase.N-terminal DNA-binding domain of lambda integrase.GCC-box DNA-binding domains of certain transcription factors.Methyl-CpG DNA-binding domain found in Methyl-CpG-binding protein 2 (MECP2) and methylation-dependent transcriptional repressor MBD1/PCM1.