Structure of human Bcl11b protein. A: The bar represents the 3 isoforms of Bcl11a. Exons 1-3 are the same in all the 3 isoforms. Isoform 1 is the longest one containing 835 amino acids. The 4th exon contains all the 6 Zinc-fingers domains. The longest isoform comprised exons 1-4, whereas the 2 common shorter isoforms exhibited alternative splicing from within exon 4 to an additional exon 5. B: The bar represents the isoform 1 of Bcl11b including 4 exons and 6 Zinc-finger domains. All the 6 Zinc-finger domains are distributed within the longest exon 4, and the exons 1–3 are in length of 214 amino acids. The 2nd and 3rd Zinc-finger domains are responsible for DNA binding. The regions shown by lines encodes domains that bind to various Bcl11b cooperating proteins, such as HDAC1/2 (histone deacetylase), SIRT2 (sirtuin family protein), SUV39H1 (histone methyltransferase), MTA1/2 (metastasis-associated proteins), RbAp46/48 (Rb-associated protein).