Fluorescence photobleaching recovery measurements of surface lateral mobilities on normal and SV40-transformed mouse fibroblasts

Abstract

Lateral mobilities of fluorescent cell surface probes were measured on normal (3T3) and transformed (SV3T3) cultured mouse fibroblasts. There is little discernible difference in the mobilities of a lipid analog (diI), a fluorescent ganglioside derivative (GM1), and tetramethylrhodamine-labeled succinylated concanavalin[Con] A. The 2 cell lines showed expected differences in their abilities to grow in agar, to grow without serum and to be agglutinated by lectins. This indicats that changes of these properties in transformed cells are probably not mediated through increased overall membrane fluidity but are associated with distinct alterations in the mobilities of cell surface receptors. Both fluorescent dextran derivatives and anti-mouse cell surface antibodies were distinctly less mobile on SV3T3 cells, and the mobile fraction of Con A receptors was lower on SV3T3 cells.