Sequence alignment of Hs-Smooth Myosin II (Hs-SMM) and different human myosins. Out of 24 residues that directly interact with CK-571, 10 are not conserved in HsMyoVI, 10 are not conserved in MyoXVIIIa, 7 are not conserved in MyoVIIa, 5 are not conserved in MyoVa, and 7 are not conserved in MyoX. Residues involved in CK-571 binding are labeled with a star. Residues that are similar but not identical are in blue; residues that are not conserved are in yellow.