title: Dynamic relationship of focal contacts and hemidesmosome protein complexes in live cells.
abstract: Epidermal cells adhere to the basement membrane zone through cell-matrix junctions termed hemidesmosomes. During wound healing, hemidesmosomes are disassembled to allow keratinocytes to move over wound sites. Such movement is mediated by both hemidesmosome protein complexes (HPCs) and focal contacts (FCs). In this study, we analyzed the interaction between HPCs and FCs in live HaCat cells expressing yellow fluorescent protein (YFP)-tagged beta4 integrin and cyan fluorescent protein (CFP)-tagged alpha-actinin as markers of HPCs and FCs, respectively. In HaCat cells migrating to repopulate wounds, FC proteins cluster rapidly in the direction of the wound. HPC assembly then follows and the newly formed HPCs occupy sites vacated by the disassembled FCs. HPC dynamics are dramatically reduced, and HaCat cells cease migration upon treatment with reagents that affect FC integrity/function. Upon treatment with reagents that destabilize HPCs, the dynamics of FCs in HaCat cells at the edges of wounds are enhanced, although FC assembly is irregular and the migration of the cells is aberrant. We also show that the complex interaction between hemidesmosomes and FCs in keratinocytes is myosin dependent and requires energy. In summary, we suggest that HPCs and FCs dynamics are tightly co-regulated in keratinocytes undergoing migration during wound healing.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Osaka City University Graduate School of Medicine, Asahimachi, Abeno-ku, Osaka, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Ozawa
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tsuruta
authors.forename: Jonathan C R
authors.initials: JC
authors.lastname: Jones
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Ishii
authors.forename: Kazuo
authors.initials: K
authors.lastname: Ikeda
authors.forename: Teruichi
authors.initials: T
authors.lastname: Harada
authors.forename: Yumi
authors.initials: Y
authors.lastname: Aoyama
authors.forename: Akira
authors.initials: A
authors.lastname: Kawada
authors.forename: Hiromi
authors.initials: H
authors.lastname: Kobayashi
mesh_terms: D000185:Actinin / Q000378:metabolism; D015703:Antigens, CD / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D002450:Cell Communication / Q000502:physiology*; D002460:Cell Line; D002465:Cell Movement / Q000502:physiology*; D005456:Fluorescent Dyes; D022001:Focal Adhesions / Q000502:physiology*; D022002:Hemidesmosomes / Q000502:physiology*; D006801:Humans; D039663:Integrin beta4 / Q000378:metabolism; D015603:Keratinocytes / Q000502:physiology*; D009218:Myosins / Q000378:metabolism; D051190:Plectin / Q000378:metabolism; D060185:Tetraspanin 24; D014945:Wound Healing / Q000502:physiology
chemical_list: D015703:Antigens, CD; D015415:Biomarkers; C554715:CD151 protein, human; D005456:Fluorescent Dyes; D039663:Integrin beta4; D051190:Plectin; D060185:Tetraspanin 24; D000185:Actinin; D009218:Myosins