COLOCALIZATION OF GLUCOKINASE WITH ACTIN-FILAMENTS

A portion of glucokinase appeared to be co-localized with actin filame nts in the cytoplasm of cultured rat hepatocytes incubated with 25 mM glucose, When liver- or islet-type glucokinase was transiently express ed in COS-7 cells, the expressed glucokinase mas also co-localized wit h actin filaments in the cytoplasm of these transfected cells, Althoug h colocalization of glucokinase with actin filaments was not clearly d emonstrated in the pancreatic beta-cell line MIN6, islet glucokinase w as found to be present in both the nucleus and the cytoplasm, though p redominantly in the nucleus, These findings suggest that subcellular l ocalization of glucokinase, including colocalization with actin filame nts, may have an important physiological role in metabolic regulation. (C) 1997 Federation of European Biochemical Societies.