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APC2 controls dendrite development by promoting microtubule dynamics.

ABSTRACT: Mixed polarity microtubule organization is the signature characteristic of vertebrate dendrites. Oppositely oriented microtubules form the basis for selective cargo trafficking in neurons, however the mechanisms that establish and maintain this organization are unclear. Here, we show that APC2, the brain-specific homolog of tumor-suppressor protein adenomatous polyposis coli (APC), promotes dynamics of minus-end-out microtubules in dendrites. We found that APC2 localizes as distinct clusters along microtubule bundles in dendrites and that this localization is driven by LC8-binding and two separate microtubule-interacting domains. Depletion of APC2 reduces the plus end dynamics of minus-end-out oriented microtubules, increases microtubule sliding, and causes defects in dendritic morphology. We propose a model in which APC2 regulates dendrite development by promoting dynamics of minus-end-out microtubules.

SUBMITTER: Kahn OI

PROVIDER: S-EPMC6050278 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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APC2 controls dendrite development by promoting microtubule dynamics.

Kahn Olga I OI Schätzle Philipp P van de Willige Dieudonnée D Tas Roderick P RP Lindhout Feline W FW Portegies Sybren S Kapitein Lukas C LC Hoogenraad Casper C CC

Nature communications 20180717 1

Mixed polarity microtubule organization is the signature characteristic of vertebrate dendrites. Oppositely oriented microtubules form the basis for selective cargo trafficking in neurons, however the mechanisms that establish and maintain this organization are unclear. Here, we show that APC2, the brain-specific homolog of tumor-suppressor protein adenomatous polyposis coli (APC), promotes dynamics of minus-end-out microtubules in dendrites. We found that APC2 localizes as distinct clusters alo ...[more]

PMID: 30018294

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