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The O-GlcNAc Transferase Intellectual Disability Mutation L254F Distorts the TPR Helix.

ABSTRACT: O-linked ?-N-acetyl-D-glucosamine (O-GlcNAc) transferase (OGT) regulates protein O-GlcNAcylation, an essential post-translational modification that is abundant in the brain. Recently, OGT mutations have been associated with intellectual disability, although it is not understood how they affect OGT structure and function. Using a multi-disciplinary approach we show that the L254F OGT mutation leads to conformational changes of the tetratricopeptide repeats and reduced activity, revealing the molecular mechanisms contributing to pathogenesis.

SUBMITTER: Gundogdu M

PROVIDER: S-EPMC5967971 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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The O-GlcNAc Transferase Intellectual Disability Mutation L254F Distorts the TPR Helix.

Gundogdu Mehmet M Llabrés Salomé S Gorelik Andrii A Ferenbach Andrew T AT Zachariae Ulrich U van Aalten Daan M F DMF

Cell chemical biology 20180329 5

O-linked β-N-acetyl-D-glucosamine (O-GlcNAc) transferase (OGT) regulates protein O-GlcNAcylation, an essential post-translational modification that is abundant in the brain. Recently, OGT mutations have been associated with intellectual disability, although it is not understood how they affect OGT structure and function. Using a multi-disciplinary approach we show that the L254F OGT mutation leads to conformational changes of the tetratricopeptide repeats and reduced activity, reveali ...[more]

PMID: 29606577

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