BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in zinc finger and BTB domain-containing protein 4 (ZBTB4)
ZBTB4, also called KAISO-like zinc finger protein 1 (KAISO-L1), is a transcriptional repressor with bimodal DNA-binding specificity. It binds with a higher affinity to methylated CpG dinucleotides in the consensus sequence 5'-CGCG-3' but can also bind to the non-methylated consensus sequence 5'-CTGCNA-3', also known as the consensus kaiso binding site (KBS). It can also bind specifically to a single methyl-CpG pair and can bind hemimethylated DNA but with a lower affinity compared to methylated DNA. ZBTB4 contains a BTB/POZ domain, a common protein-protein interaction motif of about 100 amino acids.