Myosins are actin-based motor molecules with ATPase activity. Unconventional myosins serve in intracellular movements. Their highly divergent tails are presumed to bind to membranous compartments, which would be moved relative to actin filaments. Involved in glucose transporter recycling in response to insulin by regulating movement of intracellular GLUT4-containing vesicles to the plasma membrane. Component of the hair cell's (the sensory cells of the inner ear) adaptation-motor complex. Acts as a mediator of adaptation of mechanoelectrical transduction in stereocilia of vestibular hair cells. Binds phosphoinositides and links the actin cytoskeleton to cellular membranes (By similarity). Isoform 3 is involved in regulation of transcription. Associated with transcriptional active ribosomal genes. Appears to cooperate with the WICH chromatin-remodeling complex to facilitate transcription. Necessary for the formation of the first phosphodiester bond during transcription initiation (By similarity). Interacts with RPS6 and actin. Interacts (via its IQ motifs) with CABP1 and CIB1; the interaction with CABP1 and CIB1 is calcium-dependent. Interacts (via tail domain) with PLEKHB1 (via PH domain); the interaction is not affected by the presence or absence of calcium and CALM. Interacts with POLR1A and POLR2A. Component of the B-WICH complex, at least composed of SMARCA5/SNF2H, BAZ1B/WSTF, SF3B1, DEK, MYO1C, ERCC6, MYBBP1A and DDX21. Interacts with YWHAB; this precludes interaction with CALM. Likewise, interaction with CALM precludes interaction with YWHAB (By similarity). Interacts (via its IQ motifs) with CALM. Interacts with LLPH (By similarity). Colocalizes with CABP1 and CIB1 at cell margin, membrane ruffles and punctate regions on the cell membrane. Colocalizes in adipocytes with GLUT4 at actin-based membranes. Colocalizes with GLUT4 at insulin-induced ruffles at the cell membrane. Localizes transiently at cell membrane to region known to be enriched in PIP2. Activation of phospholipase C results in its redistribution to the cytoplasm (By similarity). In the nucleolus, is localized predominantly in dense fibrillar component (DFC) and in granular component (GC). Accumulates strongly in DFC and GC during activation of transcription. Colocalizes with transcription sites. Colocalizes in the granular cortex at the periphery of the nucleolus with RPS6. Colocalizes in nucleoplasm with RPS6 and actin that are in contact with RNP particles. Colocalizes with RPS6 at the nuclear pore level. Colocalizes with RNA polymerase II in the nucleus. Colocalizes with RNA polymerase I in nucleoli (By similarity). Widely expressed. Binds directly to large unilamellar vesicles (LUVs) containing phosphatidylinositol 4,5-bisphosphate (PIP2) or inositol 1,4,5-trisphosphate (InsP3). The PIP2-binding site corresponds to the myosin tail domain (PH-like) present in its tail domain (By similarity). Isoform 2 contains a N-acetylmethionine at position 1. Belongs to the TRAFAC class myosin-kinesin ATPase superfamily. Myosin family. Represents an unconventional myosin. This protein should not be confused with the conventional myosin-1 (MYH1).