Elevated O-GlcNAc modification of proteins in diabetic kidney

Y. Akimoto, Y. Miura, T. Toda, M.A. Wolfert, L. Wells, G.-J. Boons, G.W. Hart, T. Endo, H. Kawakami

    Research output: Contribution to journalArticleAcademicpeer-review


    Increased flux through the hexosamine biosynthesis pathway promotes the modification of proteins by O-linked N-acetylglucosamine (O-GlcNAc). In our previous immunohistochemical study, we demonstrated that the extent of O-GlcNAcylation was increased in kidneys from diabetic GK rats. In the present study, to identity marker proteins that change in their extent of O-GlcNAcylation in the diabetic kidney from GK rats, we separated total kidney proteins by two-dimensional gel electrophoresis. O-GlcNAcylated proteins that changed significantly in the degree of O-GlcNAcylation were identified as cytoskeletal proteins (alpha-actin, alpha-tubulin, alpha-actinin 4, myosin) and mitochondrial proteins (ATP synthase beta, pyruvate carboxylase). This is the first report to show that alpha-actinin 4, whose mutation causes familiar segmental glomerulosclerosis (FSGS), is O-GlcNAcylated. Results of immunoprecipitation and immunoblot studies, as well as in situ Proximity Ligation Assays demonstrated that the extent of O-GlcNAcylation of the above proteins increased in the diabetic kidney. Immunofluorescence studies revealed that the levels of immunoreactivity of actin, alpha-actinin 4 and myosin were markedly increased in the glomerulus of the diabetic kidney. In contrast, the level of immunoreactive alpha-tubulin was concomitantly decreased in the proximal tubule of the diabetic kidney. Immunoelectron microscopy revealed that immunolabeling of alpha-actinin 4 increased in the foot process of podocytes. These results suggest that changes in the O-GlcNAcylation of cytoskeletal proteins are closely associated with the morphological changes in the podocyte foot processes in the glomerulus and in microvilli of proximal tubules in the diabetic kidney.
    Original languageEnglish
    Pages (from-to)260-261
    Number of pages2
    JournalGlycoconjugate Journal
    Issue number5
    Publication statusPublished - 1 Jul 2011


    • protein
    • glycoconjugate
    • alpha actinin 4
    • alpha tubulin
    • cytoskeleton protein
    • myosin
    • actin
    • pyruvate carboxylase
    • hexosamine
    • n acetylglucosamine
    • marker
    • mitochondrial protein
    • proton transporting adenosine triphosphate synthase
    • kidney
    • diabetes mellitus
    • glomerulus
    • kidney proximal tubule
    • podocyte
    • Goto Kakizaki rat
    • mutation
    • focal glomerulosclerosis
    • immunoprecipitation
    • immunoblotting
    • ligation
    • immunofluorescence
    • immunoreactivity
    • immunoelectron microscopy
    • antibody labeling
    • microvillus
    • biosynthesis
    • identity
    • two dimensional gel electrophoresis
    • assay


    Dive into the research topics of 'Elevated O-GlcNAc modification of proteins in diabetic kidney'. Together they form a unique fingerprint.

    Cite this