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Protein clustering for cell polarity: Par-3 as a paradigm.

ABSTRACT: The scaffold protein Par-3 ( Drosophila Bazooka) is a central organizer of cell polarity across animals. This review focuses on how the clustering of Par-3 contributes to cell polarity. It begins with the Par-3 homo-oligomerization mechanism and its regulation by Par-1 phosphorylation. The role of polarized cytoskeletal networks in distributing Par-3 clusters to one end of the cell is then discussed, as is the subsequent maintenance of polarized Par-3 clusters through hindered mobility and inhibition from the opposite pole. Finally, specific roles of Par-3 clusters are reviewed, including the bundling of microtubules, the cortical docking of centrosomes, the growth and positioning of cadherin-catenin clusters, and the inhibition of the Par-6-aPKC kinase cassette. Examples are drawn from Drosophila, Caenorhabditis elegans, mammalian cell culture, and biochemical studies.

SUBMITTER: Harris TJC

PROVIDER: S-EPMC5583741 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Protein clustering for cell polarity: Par-3 as a paradigm.

Harris Tony J C TJC

F1000Research 20170831

The scaffold protein Par-3 ( <i>Drosophila</i> Bazooka) is a central organizer of cell polarity across animals. This review focuses on how the clustering of Par-3 contributes to cell polarity. It begins with the Par-3 homo-oligomerization mechanism and its regulation by Par-1 phosphorylation. The role of polarized cytoskeletal networks in distributing Par-3 clusters to one end of the cell is then discussed, as is the subsequent maintenance of polarized Par-3 clusters through hindered mobility an ...[more]

PMID: 29026528

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