High expression of the taurine transporter TauT in primary cilia of NIH3T3 fibroblasts.
Taurine, present in high concentrations in various mammalian cells, is essential for regulation of cell volume, cellular oxidative status as well as the cellular Ca2+ homeostasis. Cellular taurine content is a balance between active uptake through the saturable, Na(+)-dependent taurine transporter TauT, and passive release via a volume-sensitive leak pathway. Here we demonstrate that: (i) TauT localizes to the primary cilium of growth-arrested NIH3T3 fibroblasts, (ii) long-term exposure to TNF(alpha) or hypertonic sucrose medium, i.e., growth medium supplemented with 100 mM sucrose, increases ciliary TauT expression and (iii) long-term exposure to hypertonic taurine medium, i.e., growth medium supplemented with 100 mM taurine, reduces ciliary TauT expression. These results point to an important role of taurine in the regulation of physiological processes located to the primary cilium.
Christensen
Søren T
ST
Institute of Molecular Biology and Physiology, The August Krogh Building, Department of Biochemistry, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen OE, Denmark. stchristensen@aki.ku.dk
Voss
Jesper W
JW
Teilmann
Stefan C
SC
Lambert
Ian H
IH
D016475:3T3 Cells; D000818:Animals; D002478:Cells, Cultured; D002923:Cilia / Q000187:drug effects / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology* / Q000187:drug effects; D008562:Membrane Glycoproteins / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000378:metabolism*; D051379:Mice; D013395:Sucrose / Q000494:pharmacology; D013654:Taurine / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D000099247:Taurine Transporters
D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D013395:Sucrose; D013654:Taurine; D014409:Tumor Necrosis Factor-alpha; D000099247:Taurine Transporters