A, Diagram showing the regions in the Myo1b molecule targeted by shRNAs 242, 628, and 891. The region of the Myo1b gene cloned from opossum, which includes the C-terminal region of the motor domain, the entire light chain-binding or “IQ” domain, and a portion of the tail region, is indicated. B, Immunoblot showing reduced Myo1b expression in OK 3B/2 cells expressing Myo1b-specific shRNAs 243, 628 and 891. Tubulin (T) was used as a loading standard. C, Phalloidin-stained patched microvilli on the apical surface of cells transfected with empty vector (Mock) resembled those on Myo1b-kd cells (243, 628, 891) indicating that Myo1b kd does not affect microvillar integrity. Scale bar = 10 μm.