title: Activated full-length myosin-X moves processively on filopodia with large steps toward diverse two-dimensional directions.
abstract: Myosin-X, (Myo 10), is an unconventional myosin that transports the specific cargos to filopodial tips, and is associated with the mechanism underlying filopodia formation and extension. To clarify the innate motor characteristic, we studied the single molecule movement of a full-length myosin-X construct with leucine zipper at the C-terminal end of the tail (M10FullLZ) and the tail-truncated myosin-X without artificial dimerization motif (BAP-M101-979HMM). M10FullLZ localizes at the tip of filopodia like myosin-X full-length (M10Full). M10FullLZ moves on actin filaments in the presence of PI(3,4,5)P3, an activator of myosin-X. Single molecule motility analysis revealed that the step sizes of both M10FullLZ and BAP-M101-979HMM are widely distributed on single actin filaments that is consistent with electron microscopy observation. M10FullLZ moves on filopodial actin bundles of cells with a mean step size (~36 nm), similar to the step size on single actin filaments (~38 nm). Cartesian plot analysis revealed that M10FullLZ meandered on filopodial actin bundles to both x- and y- directions. These results suggest that the lever-arm of full-length myosin-X is flexible enough to processively steps on different actin filaments within the actin bundles of filopodia. This characteristic of myosin-X may facilitate actin filament convergence for filopodia production.
authors.affiliation: Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, 11937 US HWY 271, Tyler, Texas 75708, USA.
authors.forename: Osamu
authors.initials: O
authors.lastname: Sato
authors.affiliation: Department of Biochemistry, College of Natural Sciences, Kangwon National University, 1, Kangwondaehak-gil, Chuncheon-si, Gangwon-do 24341, Korea.
authors.forename: Hyun Suk
authors.initials: HS
authors.lastname: Jung
authors.affiliation: Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, 11937 US HWY 271, Tyler, Texas 75708, USA.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Komatsu
authors.affiliation: Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, 11937 US HWY 271, Tyler, Texas 75708, USA.|Department of Pharmacology, University of Illinois College of Medicine, 808 S Wood St., Chicago, Illinois 60612, USA.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Tsukasaki
authors.affiliation: Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, 11937 US HWY 271, Tyler, Texas 75708, USA.|Laboratory for Comprehensive Bioimaging, RIKEN Quantitative Biology Center, 6-2-3, Furuedai, Suita, Osaka 565-0874, Japan.
authors.forename: Tomonobu M
authors.initials: TM
authors.lastname: Watanabe
authors.affiliation: Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, 11937 US HWY 271, Tyler, Texas 75708, USA.|Department of Otolaryngology-Head and Neck Surgery, Feinberg School of Medicine, Knowles Hearing Center, Northwestern University, 320 E Superior, Chicago, Illinois 60611, USA.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Homma
authors.affiliation: Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, 11937 US HWY 271, Tyler, Texas 75708, USA.
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Ikebe
mesh_terms: D008841:Actin Cytoskeleton / Q000235:genetics / Q000378:metabolism*; D020816:Amino Acid Motifs; D000818:Animals; D002417:Cattle; D002460:Cell Line; D051379:Mice; D009218:Myosins / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport / Q000502:physiology; D011554:Pseudopodia / Q000235:genetics / Q000378:metabolism*
chemical_list: C409064:Myo10 protein, mouse; D009218:Myosins