The relationship between high-affinity binding of cytochalasin B to 3T3 cells and inhibition of sugar transport and cell motility

• Published in: Journal of receptor research Vol. 1; no. 2; p. 113
• Main Authors: Atlas, S J, Magargal, W W, Lin, S
• Format: Journal Article
• Language: English
• Published: United States 1980
• Subjects: Animals; Binding, Competitive; Biological Transport - drug effects; Carbohydrate Metabolism; Cell Line; Cell Movement - drug effects; Cytochalasin B - metabolism; Cytochalasins - pharmacology; Deoxyglucose - metabolism; Mice; Mice, Inbred BALB C; Phloretin - pharmacology; Phlorhizin - pharmacology
• ISSN: 0197-5110
• DOI: 10.3109/10799898009044095

Transport and motility inhibitors have been used to classify different types of high-affinity cytochalasin B (CB) binding sites in 3T3 cells. The potency of phloretin and phlorizin as inhibitors of sugar uptake paralleled their effectiveness in displacing high-affinity bound CB from the cells, indicating that the two compounds compete with CB for binding to sites associated with sugar transport proteins. On the other hand, cytochalasins D and E, which did not inhibit sugar uptake, inhibited binding of CB to a portion of the high-affinity sites, most probably those associated with actin-containing cytoskeletal-contractile structures. A small amount of high-affinity CB binding remained in the presence of both phloretin and cytochalasin E, indicating that the cells have a third class of sites which is not related to either sugar transport or cell motility, When isolated membranes were examined, it was found that a fraction of each class of high-affinity CB binding sites were associated with the fraction. In contrast, only sites sensitive to cytochalasin D were recovered in a soluble extract of the cells.