Involved in skeletal muscle development and differentiation. Regulates proliferation and differentiation of myoblasts and plays a role in myofibril assembly by promoting lateral fusion of adjacent thin fibrils into mature, wide myofibrils. Required for pseudopod elongation in transformed cells. Interacts with NRAP. Part of a complex that contains CUL3, RBX1 and KLHL41. Interacts with LASP1. Predominantly cytoplasmic but can colocalize with F-actin at the membrane ruffle-like structures at the tips of transformation-specific pseudopodia. Skeletal muscle. Localized between laterally fusing myofibrils in skeletal muscle (at protein level). Expressed at a lower level in the heart compared to skeletal muscle. Expressed in the myotome part of the mature somites in embryos from embryonic day 9.5 onwards. It is not expressed in the developing heart at these embryonic stages. Ubiquitinated by E3 ubiquitin ligase complex formed by CUL3 and RBX1 and probably targeted for proteasome-independent degradation. Quinone-induced oxidative stress increases its ubiquitination.