title: Rotation is the primary motion of paired human epidermal keratinocytes.
abstract: BACKGROUND
  Collective motion of keratinocytes is involved in morphogenesis, homeostasis, and wound healing of the epidermis. Yet how the collective motion of keratinocytes emerges from the behavior of individual cells is still largely unknown.
  
  
  OBJECTIVE
  The aim of this study was to find the cellular behavior that links single and collective motion of keratinocytes.
  
  
  METHODS
  We investigated the behavior of two-cell colonies of HaCaT keratinocytes by a combination of time-lapse imaging and image processing.
  
  
  RESULTS
  The two-cell colonies of HaCaT cells were formed as a contacted pair of keratinocyte clones. Image analysis and cell culture experiments revealed that the rotational speed of two-cell colonies was positively associated with their proliferative capacity. α6 integrin was required for the rotational motion of two-cell keratinocyte colonies. We also confirmed that two-cell colonies of keratinocytes predominantly exhibited the rotational, but not translational, motion, two modes of motion in a contact pair of rotating objects.
  
  
  CONCLUSIONS
  The rotational motion is the primary motion of two-cell keratinocyte colonies and its speed is positively associated with their proliferative capacity. This study suggests that the assembly of rotating keratinocytes generates the collective motion of proliferative keratinocytes during morphogenesis and wound healing of the epidermis.
authors.affiliation: Department of Biochemistry and Molecular Genetics, Graduate School of Medicine, Ehime University, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Sota
authors.initials: S
authors.lastname: Tate
authors.affiliation: Department of Biochemistry and Molecular Genetics, Graduate School of Medicine, Ehime University, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Matome
authors.initials: M
authors.lastname: Imai
authors.affiliation: Translational Research Center, Ehime University Hospital, Ehime University, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Natsuki
authors.initials: N
authors.lastname: Matsushita
authors.affiliation: Department of Stem Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
authors.forename: Emi K
authors.initials: EK
authors.lastname: Nishimura
authors.affiliation: Department of Biochemistry and Molecular Genetics, Graduate School of Medicine, Ehime University, Shitsukawa, Toon, Ehime 791-0295, Japan; Division of Cell Growth and Tumor Regulation, Proteo-Science Center (PROS), Ehime University, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Higashiyama
authors.affiliation: Department of Biochemistry and Molecular Genetics, Graduate School of Medicine, Ehime University, Shitsukawa, Toon, Ehime 791-0295, Japan; Division of Cell Growth and Tumor Regulation, Proteo-Science Center (PROS), Ehime University, Shitsukawa, Toon, Ehime 791-0295, Japan; Department of Stem Cell Biology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan. Electronic address: nanbscm@tmd.ac.jp.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Nanba
mesh_terms: D002460:Cell Line; D002465:Cell Movement / Q000235:genetics / Q000502:physiology*; D049109:Cell Proliferation; D002999:Clone Cells; D018920:Coculture Techniques; D006801:Humans; D007091:Image Processing, Computer-Assisted; D039503:Integrin alpha6 / Q000235:genetics*; D015603:Keratinocytes / Q000502:physiology*; D012399:Rotation; D059008:Time-Lapse Imaging
chemical_list: D039503:Integrin alpha6
keywords: Cellular dynamics; Hacat cells; Keratinocytes; Proliferative capacity; Rotational motion