title: GFAP isoforms control intermediate filament network dynamics, cell morphology, and focal adhesions.
abstract: Glial fibrillary acidic protein (GFAP) is the characteristic intermediate filament (IF) protein in astrocytes. Expression of its main isoforms, GFAPα and GFAPδ, varies in astrocytes and astrocytoma implying a potential regulatory role in astrocyte physiology and pathology. An IF-network is a dynamic structure and has been functionally linked to cell motility, proliferation, and morphology. There is a constant exchange of IF-proteins with the network. To study differences in the dynamic properties of GFAPα and GFAPδ, we performed fluorescence recovery after photobleaching experiments on astrocytoma cells with fluorescently tagged GFAPs. Here, we show for the first time that the exchange of GFP-GFAPδ was significantly slower than the exchange of GFP-GFAPα with the IF-network. Furthermore, a collapsed IF-network, induced by GFAPδ expression, led to a further decrease in fluorescence recovery of both GFP-GFAPα and GFP-GFAPδ. This altered IF-network also changed cell morphology and the focal adhesion size, but did not alter cell migration or proliferation. Our study provides further insight into the modulation of the dynamic properties and functional consequences of the IF-network composition.
authors.affiliation: Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.
authors.forename: Martina
authors.initials: M
authors.lastname: Moeton
authors.affiliation: Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.|Soft Tissue Biomechanics & Engineering, Department of biomedical engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
authors.forename: Oscar M J A
authors.initials: OM
authors.lastname: Stassen
authors.affiliation: Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG, Utrecht, The Netherlands.
authors.forename: Jacqueline A
authors.initials: JA
authors.lastname: Sluijs
authors.affiliation: Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.
authors.forename: Vincent W N
authors.initials: VW
authors.lastname: van der Meer
authors.affiliation: Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.
authors.forename: Liselot J
authors.initials: LJ
authors.lastname: Kluivers
authors.affiliation: Physics of Life Processes, Leiden Institute of Physics, Leiden, The Netherlands.
authors.forename: Hedde
authors.initials: H
authors.lastname: van Hoorn
authors.affiliation: Physics of Life Processes, Leiden Institute of Physics, Leiden, The Netherlands.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmidt
authors.affiliation: Cell Biology and Histology, AMC Medical Center, Amsterdam, The Netherlands.
authors.forename: Eric A J
authors.initials: EA
authors.lastname: Reits
authors.affiliation: Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.|Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG, Utrecht, The Netherlands.
authors.forename: Miriam E
authors.initials: ME
authors.lastname: van Strien
authors.affiliation: Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands. e.m.hol-2@umcutrecht.nl.|Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG, Utrecht, The Netherlands. e.m.hol-2@umcutrecht.nl.|Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands. e.m.hol-2@umcutrecht.nl.
authors.forename: Elly M
authors.initials: EM
authors.lastname: Hol
mesh_terms: D000199:Actins / Q000378:metabolism; D000328:Adult; D000368:Aged; D001253:Astrocytes / Q000166:cytology* / Q000378:metabolism; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D048430:Cell Shape; D002470:Cell Survival; D005260:Female; D022001:Focal Adhesions / Q000378:metabolism*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D021621:Imaging, Three-Dimensional; D007382:Intermediate Filaments / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism; D064231:Nestin / Q000378:metabolism; D020033:Protein Isoforms / Q000378:metabolism; D014746:Vimentin / Q000378:metabolism
chemical_list: D000199:Actins; D005904:Glial Fibrillary Acidic Protein; D064231:Nestin; D020033:Protein Isoforms; D014746:Vimentin; D049452:Green Fluorescent Proteins
keywords: Astrocytoma; FRAP; GFAP; Intermediate filaments