title: Nuclear localization of liver FBPase isoenzyme in kidney and liver.
abstract: Nuclear localization has been observed for glycolytic enzymes but not for key gluconeogenic enzymes. We report our findings on the intracellular localization of liver FBPase in rat liver and kidney, the main organs in the endogenous glucose production. Immunofluorescence and confocal analysis revealed that FBPase was present in the cytosol and, unexpectedly, inside the nucleus of hepatocytes and proximal cells of the nephron. Additionally, FBPase was found in the plasma membrane area of adjacent hepatocytes where glycogen is synthesized and in the apical region of proximal kidney cells. This subcellular distribution in multiple compartments suggests the presence of different localization signals on FBPase for diverse metabolic functions.
authors.affiliation: Instituto de Bioquímica, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile.
authors.forename: Alejandro J
authors.initials: AJ
authors.lastname: Yáñez
authors.forename: Romina
authors.initials: R
authors.lastname: Bertinat
authors.forename: Ilona I
authors.initials: II
authors.lastname: Concha
authors.forename: Juan C
authors.initials: JC
authors.lastname: Slebe
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D002467:Cell Nucleus / Q000201:enzymology*; D005455:Fluorescent Antibody Technique; D006597:Fructose-Bisphosphatase / Q000276:immunology / Q000378:metabolism*; D015151:Immunoblotting; D007527:Isoenzymes / Q000276:immunology / Q000378:metabolism; D007668:Kidney / Q000166:cytology / Q000201:enzymology*; D008099:Liver / Q000166:cytology / Q000201:enzymology*; D018613:Microscopy, Confocal; D051381:Rats; D011919:Rats, Inbred Strains; D014020:Tissue Extracts
chemical_list: D007527:Isoenzymes; D014020:Tissue Extracts; D006597:Fructose-Bisphosphatase