Impact of the Reduced Folate Carrier on the Accumulation of Active Thiamin Metabolites in Murine Leukemia Cells*

@article{Zhao2001ImpactOT,
  title={Impact of the Reduced Folate Carrier on the Accumulation of Active Thiamin Metabolites in Murine Leukemia Cells*},
  author={Rongbao Zhao and Feng Gao and Yanhua Wang and George A Diaz and Bruce D. Gelb and I. David Goldman},
  journal={The Journal of Biological Chemistry},
  year={2001},
  volume={276},
  pages={1114 - 1118}
}
The thiamin transporter encoded bySLC19A2 and the reduced folate carrier (RFC1) share 40% homology at the protein level, but the thiamin transporter does not mediate transport of folates. By using murine leukemia cell lines that express no, normal, or high levels of RFC1, we demonstrate that RFC1 does not mediate thiamin influx. However, high level RFC1 expression substantially reduced accumulation of the active thiamin coenzyme, thiamin pyrophosphate (TPP). This decreased level of TPP… 

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  • S. Nabokina, H. Said
  • Biology
    American journal of physiology. Gastrointestinal and liver physiology
  • 2012
TLDR
The findings suggest the involvement of a carrier-mediated mechanism for TPP uptake by colonic NCM460 cells, which was further confirmed by results from studies of native human colonic apical membrane vesicles, and suggest that the bacterially synthesized TPP in the large intestine is bioavailable and may contribute to overall body homeostasis of vitamin B1 and to the cellular nutrition of the local colonocytes.
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