Diffusion of injected macromolecules within the cytoplasm of living cells

摘要: Abstract The diffusion of macromolecules introduced into the cytoplasm human fibroblasts by erythrocyte-mediated microinjection was measured fluorescence recovery after photobleaching technique. The apparent coefficients for fluorescein-labeled IgG and bovine serum albumin were approximately 10(-8) cm2/sec at 22 degrees C, consistent with kinetics spreading fluorescent probe following 1/70 values in aqueous buffer. labeled shown to be strongly dependent on temperature and, fact, similar that expected a 61% sucrose solution. However, marked reduction 5 C could fully reversed incubation 0.1 mM colchicine. These findings suggest cytoplasmic rates are reduced relative media as result increased phase viscosity or impedence provided structural elements. Several simple models account data presented.