title: Annexin II modulates volume-activated chloride currents in vascular endothelial cells.
abstract: The membrane-associated, microfilament-binding protein annexin II is abundantly expressed in endothelial cells from calf pulmonary artery (CPAE cells). We have analyzed its role in the regulation of volume-activated chloride currents (ICl, vol) by loading the cells via the patch pipette with a peptide comprising the N-terminal 14 residues of annexin II. This sequence harbors the binding site for the intracellular annexin II ligand, p11, and the peptide interferes with the annexin II-p11 complex formation. Loading of a CPAE cell with this peptide caused a gradual decrease in the amplitude of ICl, vol during repetitive stimulations with a 28% hypotonic extracellular solution. This run down of the current was virtually absent in untreated cells and in cells that were loaded with a mutated 14-amino acid peptide, which has a single amino acid replacement known to result in a more than 1000 times reduced affinity for binding to p11. We conclude that annexin II-p11 complex formation is either directly or indirectly involved in the activation of ICl, vol in endothelial cells.
authors.affiliation: Laboratorium voor Fysiologie, KU Leuven, B-3000 Leuven, Belgium. bernd.nilius@med.kuleuven.ac.be
authors.forename: B
authors.initials: B
authors.lastname: Nilius
authors.forename: V
authors.initials: V
authors.lastname: Gerke
authors.forename: J
authors.initials: J
authors.lastname: Prenen
authors.forename: G
authors.initials: G
authors.lastname: Szücs
authors.forename: S
authors.initials: S
authors.lastname: Heinke
authors.forename: K
authors.initials: K
authors.lastname: Weber
authors.forename: G
authors.initials: G
authors.lastname: Droogmans
mesh_terms: D000818:Animals; D017306:Annexin A2 / Q000502:physiology*; D002118:Calcium / Q000502:physiology; D002417:Cattle; D002460:Cell Line; D048429:Cell Size; D018118:Chloride Channels / Q000502:physiology*; D002712:Chlorides / Q000502:physiology*; D004285:Dogs; D004730:Endothelium, Vascular / Q000502:physiology*; D010446:Peptide Fragments / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D011485:Protein Binding; D009418:S100 Proteins; D014882:Water-Electrolyte Balance; D000099248:S100 Calcium Binding Protein A10
chemical_list: D017306:Annexin A2; D002118:Calcium; D018118:Chloride Channels; D002712:Chlorides; D010446:Peptide Fragments; D010455:Peptides; D009418:S100 Proteins; D000099248:S100 Calcium Binding Protein A10