title: Myosin I links PIP3 signaling to remodeling of the actin cytoskeleton in chemotaxis.
abstract: Class I myosins participate in various interactions between the cell membrane and the cytoskeleton. Several class I myosins preferentially bind to acidic phospholipids, such as phosphatidylserine and phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], through a tail homology 1 (TH1) domain. Here, we show that the second messenger lipid phosphatidylinositol 3,4,5-trisphosphate (PIP3) binds to the TH1 domain of a subset of Dictyostelium class I myosins (ID, IE, and IF) and recruits them to the plasma membrane. The PIP3-regulated membrane recruitment of myosin I promoted chemotaxis and induced chemoattractant-stimulated actin polymerization. Similarly, PIP3 recruited human myosin IF to the plasma membrane upon chemotactic stimulation in a neutrophil cell line. These data suggest a mechanism through which the PIP3 signal is transmitted through myosin I to the actin cytoskeleton.
authors.affiliation: Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
authors.forename: Chun-Lin
authors.initials: CL
authors.lastname: Chen
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Hiromi
authors.initials: H
authors.lastname: Sesaki
authors.forename: Miho
authors.initials: M
authors.lastname: Iijima
mesh_terms: D008841:Actin Cytoskeleton / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism; D002633:Chemotaxis / Q000502:physiology*; D004023:Dictyostelium / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D018922:HL-60 Cells; D006801:Humans; D024461:Myosin Type I / Q000235:genetics / Q000378:metabolism*; D009504:Neutrophils / Q000166:cytology / Q000378:metabolism; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000235:genetics / Q000378:metabolism; D018129:Phosphatidylinositol Phosphates / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates; D015800:Protozoan Proteins; C060974:phosphatidylinositol 3,4,5-triphosphate; D024461:Myosin Type I