title: The action of small GTPases Rab11 and Rab25 in vesicle trafficking during cell migration.
abstract: BACKGROUND
  The closely related GTPases Rab11 and Rab25 promote cell migration by regulating vesicular transport and recycling of surface receptors. Rab25 carries a constitutively activating mutation in its GTPase domain. Increased expression of Rab25 has been associated with the aggressiveness of migrating tumor cells. Here, we aimed to elucidate potential differences in the role of those two GTPases in vesicle trafficking during cell migration.
  
  
  METHODS
  We expressed Rab11 and Rab25 wildtype and mutant constructs in HeLa and MDA-MB231 cells and measured their effect on cell morphology, vesicle dynamics and migration behaviour. In prostate cancer samples we analyzed the expression of both GTPases.
  
  
  RESULTS
  Cells grown on fibronectin displayed a more stretched morphology when Rab11 was inactivated, whereas inactivation of Rab25 led to reduced stretching. Overexpression of both Rab11 and Rab25 accelerated cell migration. Analysis of vesicular movement revealed higher transport efficiency in the inner cell compartment for Rab11 positive vesicles and in proximity to the membrane for Rab25 positive vesicles. Interestingly, we found Rab25 to be highly expressed in prostate cancer tissue.
  
  
  CONCLUSIONS
  Taken together, our data suggest that Rab11 is mainly responsible for basal long-distance transport from the rear end to the front of the migrating cell, whereas Rab25 acts predominantly in the small-scale fast recycling within the tips of the cell. Our results further support the idea of Rab25 as a promoter of tumor development.
authors.affiliation: Institute of Cell Biology (Cancer Research), Medical School, University of Duisburg - Essen, Essen, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Kessler
authors.forename: Gianna-Carina
authors.initials: GC
authors.lastname: Gruen
authors.forename: Dominik
authors.initials: D
authors.lastname: Heider
authors.forename: Jessica
authors.initials: J
authors.lastname: Morgner
authors.forename: Henning
authors.initials: H
authors.lastname: Reis
authors.forename: Kurt Werner
authors.initials: KW
authors.lastname: Schmid
authors.forename: Verena
authors.initials: V
authors.lastname: Jendrossek
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology*; D017931:DNA Primers; D006801:Humans; D007150:Immunohistochemistry; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009369:Neoplasms / Q000378:metabolism / Q000473:pathology; D016133:Polymerase Chain Reaction; D021381:Protein Transport; D017386:Sequence Homology, Amino Acid; D020691:rab GTP-Binding Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D000099193:rab11 GTP-Binding Proteins
chemical_list: D017931:DNA Primers; D020691:rab GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins; C509763:Rab25 protein, human