Casein kinase 2 regulates the active uptake of the organic osmolyte taurine in NIH3T3 mouse fibroblasts.
Inhibition of the constitutively active casein kinase 2 (CK2) with 2-dimethyl-amino-4,5,6,7-tetrabromo-1H-benzimidasole stimulates the Na(+)-dependent taurine influx via the taurine transporter TauT in NIH3T3 cells. CK2 inhibition reduces the TauT mRNA level and increases the localization of TauT to ER but has no detectable effect on TauT protein expression. On the other hand, CK2 inhibition increases the affinity of TauT towards Na(+ )and reduces the Na(+)/taurine stoichiometry for active taurine uptake. It is suggested that CK2 controls the cellular taurine uptake in unperturbated NIH3T3 cells, i.e., inhibition of CK2 increases the affinity of TauT towards Na(+) and hence Na(+)-dependent taurine uptake.
Department of Biology, The August Krogh Building, Universitetsparken 13, 2100, Copenhagen Ø, Denmark.
Jack H
JH
Jacobsen
Christian A
CA
Clement
Martin B
MB
Friis
Ian H
IH
Lambert
D000818:Animals; D001562:Benzimidazoles / Q000494:pharmacology; D001693:Biological Transport, Active; D047390:Casein Kinase II / Q000037:antagonists & inhibitors / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D005347:Fibroblasts / Q000187:drug effects / Q000201:enzymology*; D007700:Kinetics; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D041681:NIH 3T3 Cells; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D021381:Protein Transport; D012333:RNA, Messenger / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D013654:Taurine / Q000378:metabolism*; D014882:Water-Electrolyte Balance; D000099247:Taurine Transporters
D001562:Benzimidazoles; D047390:Casein Kinase II; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D047428:Protein Kinase Inhibitors; D012333:RNA, Messenger; D012964:Sodium; D013654:Taurine; D000099247:Taurine Transporters; C492322:2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole