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Stochastic machines as a colocalization mechanism for scaffold protein function.

ABSTRACT: The axis inhibition (Axin) scaffold protein colocalizes ?-catenin, casein kinase I?, and glycogen synthetase kinase 3? by their binding to Axin's long intrinsically disordered region, thereby yielding structured domains with flexible linkers. This complex leads to the phosphorylation of ?-catenin, marking it for destruction. Fusing proteins with flexible linkers vastly accelerates chemical interactions between them by their colocalization. Here we propose that the complex works by random movements of a "stochastic machine," not by coordinated conformational changes. This non-covalent, modular assembly process allows the various molecular machine components to be used in multiple processes.

SUBMITTER: Xue B

PROVIDER: S-EPMC4141485 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Stochastic machines as a colocalization mechanism for scaffold protein function.

Xue Bin B Romero Pedro R PR Noutsou Maria M Maurice Madelon M MM Rüdiger Stefan G D SG William Albert M AM Mizianty Marcin J MJ Kurgan Lukasz L Uversky Vladimir N VN Dunker A Keith AK

FEBS letters 20130418 11

The axis inhibition (Axin) scaffold protein colocalizes β-catenin, casein kinase Iα, and glycogen synthetase kinase 3β by their binding to Axin's long intrinsically disordered region, thereby yielding structured domains with flexible linkers. This complex leads to the phosphorylation of β-catenin, marking it for destruction. Fusing proteins with flexible linkers vastly accelerates chemical interactions between them by their colocalization. Here we propose that the complex works by random movemen ...[more]

PMID: 23603389

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