EGF triggers caveolin redistribution from the plasma membrane to the early/sorting endocytic compartment of hepatocytes

In this study, we demonstrate that, in rat Ever, epidermal growth factor (EGF) is responsible for the partial redistribution of caveolin-1 from the plasma membrane into the early/sorting endocytic compartment. Highly purified endosomes and plasma membrane fractions were isolated from control rat liver and from rats injected with EGF or pIgA for different times. Whereas in subcellular fractions from control hepatocytes most of caveolin was concentrated in the plasma membrane and the receptor-recycling fractions, after EGF injection there was a significant redistribution of caveolin toward the early/sorting (CURL) endocytic fractions. The recruitment of caveolin into the endocytic compartment was not induced by pIgA. (C) 2000 Elsevier Science Inc. All rights reserved.