Reversibility of cell surface label rearrangement
Cell surface labeling can cause rearrangements of randomly distributed membrane components. Removal of the label bound to the cell surface allows the membrane components to return to their original random distribution, demonstrating that label is necessary to maintain as well as to induce rearrangements. With scanning electron microscopy, the rearrangement of concanavalin A (con A) and ricin binding sites on LA-9 cells has been followed by means of hemocyanin, a visual label. The removal of con A from its binding sites at the cell surface with alpha- methyl mannoside, and the return of these sites to their original distribution are also followed in this manner. There are labeling differences with con A and ricin. Under some conditions, however, the same rearrangements are seen with both lectins. The disappearance of labeled sites from areas of ruffling activity is a major feature of the rearrangements seen. Both this ruffling activity and the rearrangement of label are sensitive to cytochalasin B, and ruffling activity, perhaps along with other cytochalasin-sensitive structure, may play a role in the rearrangements of labeled sites.
© 1976 by The Rockefeller University Press. Received for publication 3 April 1975, and in revised form 30 September 1975. We would like to thank Paul Bell, California Institute of Technology, for the cinematographic work he carried out in conjunction with this study. This work was supported by grants GM406-11, GM 11380 and GM 06965. It was done by Susan Smith Brown in partial fulfillment of the requirements for the Ph.D. degree at Harvard University, 1974.
Published - BROjcb76.pdf