Dataset Information

Insulin Induces Microtubule Stabilization and Regulates the Microtubule Plus-End Tracking Protein Network in Adipocytes

ABSTRACT: Insulin-stimulated glucose uptake is known to involve microtubules, although the function of microtubules and the microtubule-regulating proteins involved in insulin action are poorly understood. CLASP2, a plus-end tracking microtubule-associated protein (+TIP) that controls microtubule dynamics, was recently implicated as the first +TIP associated with insulin-regulated glucose uptake. Here, using protein-specific targeted quantitative phosphoproteomics within 3T3-L1 adipocytes, we discovered that insulin regulates phosphorylation of the CLASP2 network members G2L1, MARK2, CLIP2, AGAP3 and CKAP5 as well as EB1, revealing the existence of a previously unknown microtubule-associated protein system that responds to insulin. To further investigate, G2L1 interactome studies within 3T3-L1 adipocytes revealed that G2L1 co-immunoprecipitates CLASP2 and CLIP2 as well as the master integrators of +TIP assembly, the end binding (EB) proteins. Live-cell total internal reflection fluorescence microscopy in adipocytes revealed G2L1 and CLASP2 colocalize on microtubule plus-ends. We found that while insulin increases the number of CLASP2-containing plus-ends, insulin treatment simultaneously decreases CLASP2-containing plus-end velocity. In addition, we discovered that insulin stimulates re-distribution of CLASP2 and G2L1 from exclusive plus-end tracking to “trailing” behind the growing tip of the microtubule. Insulin treatment increases -tubulin Lysine 40 acetylation, a mechanism that was observed to be regulated by a counterbalance between GSK3 and mTOR, and also led to microtubule stabilization. Our studies introduce insulin-stimulated microtubule stabilization and plus-end trailing of +TIPs as new modes of insulin action and reveal the likelihood that a network of microtubule-associated proteins synergize to coordinate insulin-regulated microtubule dynamics.

INSTRUMENT(S): Orbitrap Fusion Lumos, LTQ Orbitrap Elite

ORGANISM(S): Rattus Norvegicus (rat) Mus Musculus (mouse)

TISSUE(S): Fat Cell, Myotube

DISEASE(S): Type 2 Diabetes Mellitus

SUBMITTER: Paul Langlais

LAB HEAD: Paul R Langlais

PROVIDER: PXD011431 | Pride | 2019-06-13

REPOSITORIES: Pride

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Publications

Insulin Induces Microtubule Stabilization and Regulates the Microtubule Plus-end Tracking Protein Network in Adipocytes.

Parker Sara S SS Krantz James J Kwak Eun-A EA Barker Natalie K NK Deer Chris G CG Lee Nam Y NY Mouneimne Ghassan G Langlais Paul R PR

Molecular & cellular proteomics : MCP 20190424 7

Insulin-stimulated glucose uptake is known to involve microtubules, although the function of microtubules and the microtubule-regulating proteins involved in insulin action are poorly understood. CLASP2, a plus-end tracking microtubule-associated protein (+TIP) that controls microtubule dynamics, was recently implicated as the first +TIP associated with insulin-regulated glucose uptake. Here, using protein-specific targeted quantitative phosphoproteomics within 3T3-L1 adipocytes, we discovered t ...[more]

PMID: 31018989

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Dataset Information

Insulin Induces Microtubule Stabilization and Regulates the Microtubule Plus-End Tracking Protein Network in Adipocytes

Publications

Insulin Induces Microtubule Stabilization and Regulates the Microtubule Plus-end Tracking Protein Network in Adipocytes.

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