Selenium distribution in mammary epithelial cells reveals its possible mechanism of inhibition of cell growth.
The subcellular and macromolecular distribution of 75Se-selenite was determined in murine mammary epithelial cell lines which demonstrated marked differences in their growth response to 5 microM selenite. MOD cells responded sooner to the inhibitory effects of selenite than COMMA-D cells. The MOD cells also incorporated a slightly higher percentage of 75Se-selenite into proteins and attained a higher ratio of selenoprotein to selenonucleic acids than did COMMA-D cells. Most selenium and selenoproteins were located in the cytoplasm as revealed by autoradiography and subcellular fractionations. These data suggest that a cytoplasmic selenoprotein may be an intermediate for selenite's nontoxic growth inhibitory effects.
D000818:Animals; D001345:Autoradiography; D002451:Cell Compartmentation; D002455:Cell Division; D002460:Cell Line; D002843:Chromatin / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D008321:Mammary Glands, Animal / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D011506:Proteins / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D012643:Selenium / Q000378:metabolism*; D051140:Selenoproteins; D013347:Subcellular Fractions / Q000378:metabolism
D002843:Chromatin; D011506:Proteins; D051140:Selenoproteins; D012313:RNA; D004247:DNA; D012643:Selenium