Polyamine Transport Systems in Mammalian Cells and Tissues
Polyamine transport plays an important role in the homeostatic regulation of the polyamine levels. In animals, dietary polyamines are absorbed efficiently in the intestinal tract. In the colon, luminal bacterial derived polyamines are important contributors to cellular polyamine contents. Polyamine transport involves unique uptake and export mechanisms. The amino acid transporter SLC3A2 acts as a polyamine exporter in colon cancer-derived cells. Polyamine uptake is mediated by caveolin-1 dependent endocytosis. The K-RAS oncogene signals increased polyamine uptake and decreased polyamine export. Here, we describe the methods of polyamine transport analysis in the colon and the small intestine using membrane vesicles, culture cells, and mouse models.
Key wordsPolyamine Putrescine Spermidine Spermine Plasma membrane vesicles Culture cells Mouse tissues Transport Colon Small intestine
We would like to thank Dr. Kirk E. Pastorian, Dr. Leo Hawel III, and Dr. Craig V. Byus, Department of Biomedical Sciences, University of California, Riverside, for development of the putrescine tolerant CHO cells. We thank Dr. B. Sloane and Dr. D. Cadavello-Medved, Department of Pharmacology, Barbara Karmanos Cancer Institute, Wayne State University, School of Medicine, for providing HCT116/Mock and HCT116/Cav-1 A. S. cells. This work was supported, in whole or in part, by National Institutes of Health Grants CA123065, and CA095060.