Role of kinesin light chain-2 of kinesin-1 in the traffic of Na,K-ATPase-containing vesicles in alveolar epithelial cells.
Recruitment of the Na,K-ATPase to the plasma membrane of alveolar epithelial cells results in increased active Na(+) transport and fluid clearance in a process that requires an intact microtubule network. However, the microtubule motors involved in this process have not been identified. In the present report, we studied the role of kinesin-1, a plus-end microtubule molecular motor that has been implicated in the movement of organelles in the Na,K-ATPase traffic. We determined by confocal microscopy and biochemical assays that kinesin-1 and the Na,K-ATPase are present in the same membranous cellular compartment. Knockdown of kinesin-1 heavy chain (KHC) or the light chain-2 (KLC2), but not of the light chain-1 (KLC1), decreased the movement of Na,K-ATPase-containing vesicles when compared to sham siRNA-transfected cells (control group). Thus, a specific isoform of kinesin-1 is required for microtubule-dependent recruitment of Na,K-ATPase to the plasma membrane, which is of physiological significance.
Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
Humberto E
HE
Trejo
Emilia
E
Lecuona
Doris
D
Grillo
Igal
I
Szleifer
Oksana E
OE
Nekrasova
Vladimir I
VI
Gelfand
Jacob I
JI
Sznajder
D056809:Alveolar Epithelial Cells / Q000502:physiology*; D002478:Cells, Cultured; D055785:Gene Knockdown Techniques; D006801:Humans; D016547:Kinesins / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000502:physiology*; D008870:Microtubules / Q000378:metabolism; D008928:Mitochondria / Q000502:physiology; D021381:Protein Transport / Q000502:physiology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D022161:Transport Vesicles / Q000378:metabolism
C488101:KIF5B protein, human; C000715688:KLC1 protein, human; D008869:Microtubule-Associated Proteins; D016547:Kinesins; D000254:Sodium-Potassium-Exchanging ATPase