Figure 2.

Alignments of the conserved KRAB and SCAN domains. (a)The KRAB domain, including both the A box and the B box. The A box is longer and more conserved than the B box. (b) The SCAN domain. This domain is found in non-zinc-finger proteins and zinc-finger proteins; the sequences shown here are for SCAN domains of KRAB-containing zinc-finger proteins. Note that these domains have a degree of conservation similar to that of the KRAB A box. Identical residues are in black, similar residues in gray and different residues in lower case. All sequences start at the first amino-acid residue.