Analysis of Na+,K+-ATPase motion and incorporation into the plasma membrane in response to G protein-coupled receptor signals in living cells.
Dopamine (DA) increases Na(+),K(+)-ATPase activity in lung alveolar epithelial cells. This effect is associated with an increase in Na(+),K(+)-ATPase molecules within the plasma membrane (). Analysis of Na(+),K(+)-ATPase motion was performed in real-time in alveolar cells stably expressing Na(+),K(+)-ATPase molecules carrying a fluorescent tag (green fluorescent protein) in the alpha-subunit. The data demonstrate a distinct (random walk) pattern of basal movement of Na(+),K(+)-ATPase-containing vesicles in nontreated cells. DA increased the directional movement (by 3.5 fold) of the vesicles and an increase in their velocity (by 25%) that consequently promoted the incorporation of vesicles into the plasma membrane. The movement of Na(+),K(+)-ATPase-containing vesicles and incorporation into the plasma membrane were microtubule dependent, and disruption of this network perturbed vesicle motion toward the plasma membrane and prevented the increase in the Na(+),K(+)-ATPase activity induced by DA. Thus, recruitment of new Na(+),K(+)-ATPase molecules into the plasma membrane appears to be a major mechanism by which dopamine increases total cell Na(+),K(+)-ATPase activity.
Bertorello
Alejandro M
AM
Department of Medicine, Atherosclerosis Research Unit, Karolinska Institutet, Karolinska Hospital, S-171 76 Stockholm, Sweden. aleber@mbox.ki.se
Komarova
Yulia
Y
Smith
Kristen
K
Leibiger
Ingo B
IB
Efendiev
Riad
R
Pedemonte
Carlos H
CH
Borisy
Gary
G
Sznajder
Jacob I
JI
D000199:Actins / Q000378:metabolism; D000818:Animals; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D016764:Cell Polarity; D022162:Cytoplasmic Vesicles / Q000378:metabolism; D004298:Dopamine / Q000494:pharmacology*; D019204:GTP-Binding Proteins / Q000378:metabolism*; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism; D017239:Paclitaxel / Q000494:pharmacology; D021381:Protein Transport / Q000502:physiology; D011650:Pulmonary Alveoli / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D020545:Respiratory Mucosa / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D000254:Sodium-Potassium-Exchanging ATPase / Q000235:genetics / Q000378:metabolism*; D013844:Thiazoles / Q000494:pharmacology; D053778:Thiazolidines
D000199:Actins; D019086:Bridged Bicyclo Compounds, Heterocyclic; D008164:Luminescent Proteins; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins; D013844:Thiazoles; D053778:Thiazolidines; D049452:Green Fluorescent Proteins; D019204:GTP-Binding Proteins; D000254:Sodium-Potassium-Exchanging ATPase; D017239:Paclitaxel; C037067:latrunculin A; D004298:Dopamine