MKL/MRTF molecules, MKL1/MRTFA [also termed megakaryocytic leukemia (MAL), basic, SAP, and coiled-coil domain (BSAC)] and MKL2/MRTFB (also termed MAL16), were identified (Sasazuki et al., 2002; Wang et al., 2002; Cen et al., 2003, 2004; Selvaraj and Prywes, 2003; Pipes et al., 2006) following the discovery of myocardin (Wang et al., 2001). Here, MRTFB is linked to leukemia.