Myo10 consists of two heavy chains with an N-terminal motor domain; a "neck" region of 3 IQ domains involved in light chain binding; a putative coiled-coil region; and a tail region containing pleckstrin homology (PH) domains, a myosin tail homology (MyTH) domain and a C-terminal FERM (4.1, ezrin, radixin, moesin) domain.
The IQ motifs bind calmodulin (CaM) or calmodulin-like light chains, which regulate Myo10 activity and Ca2+ sensitivity. Upon expression of CALML3 (in the presence of Ca2+), CALML3 competes successfully with CaM and binds tightly to IQ3 and possibly IQ1 and IQ2 of Myo10. CALML3 binding results in increased Myo10 expression and function, as demonstrated by increased filopodial extension and enhanced directional cell migration.
Sources: Caride AJ, et al. Kinetic analysis reveals differences in the binding mechanism of calmodulin and calmodulin-like protein to the IQ motifs of myosin-10. Biochemistry. 2010;49:8105, and Strehler EE. Emanuel Strehler's work on calcium pumps and calcium signaling. World Journal of Biological Chemistry. 2011;2:67.