title: Hypoxia-stimulated membrane trafficking requires T-plastin.
abstract: OBJECTIVE
  Traffic between the plasma membrane and the endomembrane compartments is an essential feature of eukaryotic cells. The secretory pathway sends cargoes from biosynthetic compartments to the plasma membrane. This is counterbalanced by a retrograde endocytic route and is essential for cell homoeostasis. Cells need to adapt rapidly to environmental challenges such as the reduction of pO2which, however, has not been analysed in relation to membrane trafficking in detail. Therefore, we determined changes in the plasma membrane trafficking in normoxia, hypoxia, and after reoxygenation.
  
  
  METHODS
  Membrane trafficking was analysed by using the bulk membrane endocytosis marker FM 1-43, the newly developed membrane probe mCLING, wheat germ agglutinin as well as fluorescently labelled cholera toxin subunit B. Additionally, the uptake of specific membrane proteins was determined. In parallel, a non-biased SILAC screen was performed to analyse the abundance of membrane proteins in normoxia and hypoxia.
  
  
  RESULTS
  Membrane trafficking was increased in hypoxia and quickly reversed upon reoxygenation. This effect was independent of the hypoxia-inducible factor (HIF) system. Using SILAC technology, we identified that the actin-bundling protein T-plastin is recruited to the plasma membrane in hypoxia. By the use of T-plastin knockdown cells, we could show that T-plastin mediates the hypoxia-induced membrane trafficking, which was associated with an increased actin density in the cells as determined by electron microscopy.
  
  
  CONCLUSIONS
  Membrane trafficking is highly dynamic upon hypoxia. This phenotype is quickly reversible upon reoxygenation, which suggests that this mechanism participates in the cellular adaptation to hypoxia.
authors.affiliation: Institute of Cardiovascular Physiology, University Medical Center Göttingen (UMG), Göttingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Wottawa
authors.affiliation: Institute of Cardiovascular Physiology, University Medical Center Göttingen (UMG), Göttingen, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Naas
authors.affiliation: Institute of Cardiovascular Physiology, University Medical Center Göttingen (UMG), Göttingen, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Böttger
authors.affiliation: Institute of Cardiovascular Physiology, University Medical Center Göttingen (UMG), Göttingen, Germany.
authors.forename: G J
authors.initials: GJ
authors.lastname: van Belle
authors.affiliation: Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany.|Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Möbius
authors.affiliation: Institute of Neuro- and Sensory Physiology, UMG, CNMPB, Göttingen, Germany.
authors.forename: N H
authors.initials: NH
authors.lastname: Revelo
authors.affiliation: Institute of Cardiovascular Physiology, University Medical Center Göttingen (UMG), Göttingen, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Heidenreich
authors.affiliation: Institute of Cardiovascular Physiology, University Medical Center Göttingen (UMG), Göttingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: von Ahlen
authors.affiliation: Institute of Cardiovascular Physiology, University Medical Center Göttingen (UMG), Göttingen, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Zieseniss
authors.affiliation: Institute of Neuro- and Sensory Physiology, UMG, CNMPB, Göttingen, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Kröhnert
authors.affiliation: Institute of Pharmacology, UMG, Göttingen, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Lutz
authors.affiliation: Bioanalytical Mass Spectrometry, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.|Bioanalytics Research Group, Institute of Clinical Chemistry, UMG, Göttingen, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Lenz
authors.affiliation: Bioanalytical Mass Spectrometry, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.|Bioanalytics Research Group, Institute of Clinical Chemistry, UMG, Göttingen, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Urlaub
authors.affiliation: Institute of Neuro- and Sensory Physiology, UMG, CNMPB, Göttingen, Germany.
authors.forename: S O
authors.initials: SO
authors.lastname: Rizzoli
authors.affiliation: Institute of Cardiovascular Physiology, University Medical Center Göttingen (UMG), Göttingen, Germany.
authors.forename: D M
authors.initials: DM
authors.lastname: Katschinski
mesh_terms: D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D006801:Humans; D000860:Hypoxia / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008840:Microfilament Proteins / Q000378:metabolism*; D021381:Protein Transport / Q000502:physiology*; D051381:Rats
chemical_list: D008562:Membrane Glycoproteins; D008840:Microfilament Proteins; C026742:plastin
keywords: T-plastin; actin bundling; hypoxia; hypoxia-inducible-factor; membrane trafficking