Myosin XI motor protein required for endoplasmic reticulum motility and protein body formation (PubMed:22892319). May function by binding with its tail domain to receptor proteins on membranes and exerting force with its N-terminal motor domain against actin filaments, thereby transporting its cargo along polarized actin cables (By similarity). Interacts (via C-terminus) with HIP (via C-terminus), but not with zeins, FL1 or intrinsic proteins of protein bodies. Associated with the endoplasmic reticulum membrane. High expression in kernels and stems, intermediate in ears and leaves, and low in roots, silks and tassels. Highly expressed in early developing kernels. IQ domain mediates interaction with calmodulin. The tail domain is a globular cargo-binding domain. Dilated endoplasmic reticulum, small and misshapen protein bodies, and opaque endosperm. Belongs to the TRAFAC class myosin-kinesin ATPase superfamily. Myosin family. Plant myosin class XI subfamily.