Monomeric myosin-XIX (Myo19) functions as an actin-based motor for mitochondrial movement in vertebrate cells []. It contains a variable number of IQ domains. Human myo19 contains a motor domain, three IQ motifs, and a short tail []. The catalytic (head) domain has ATPase activity and belongs to the larger group of P-loop NTPases. The head domain is a molecular motor with actin-activated ATPase activity [].
