Figure 8.

Homology modelled human ventricular myosin bound to cardiac actin making the ELC/actin contact at the end of the powerstroke. Three cardiac actin crystal structures in a filament in transparent grey have the top two actin monomers contacting with the myosin heavy chain (red) and the bottom actin monomer in contact with the myosin ELC N-terminus (green). Myosin RLC (transparent red) and ELC not including the N-terminus (transparent blue) are indicated. Residues in the cardiac actin sequence differing from the skeletal sequence are denoted by space-filling atoms with blue labels. Ser358 in the bottom actin monomer is proposed to form a hydrogen bond with one of the ɛ-oxygens in Glu6 (denoted by space-filling atoms with red label) from the ELC N-terminus (see figure 9).