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Huntingtin mediates dendritic transport of ?-actin mRNA in rat neurons.

ABSTRACT: Transport of mRNAs to diverse neuronal locations via RNA granules serves an important function in regulating protein synthesis within restricted sub-cellular domains. We recently detected the Huntington's disease protein huntingtin (Htt) in dendritic RNA granules; however, the functional significance of this localization is not known. Here we report that Htt and the huntingtin-associated protein 1 (HAP1) are co-localized with the microtubule motor proteins, the KIF5A kinesin and dynein, during dendritic transport of ?-actin mRNA. Live cell imaging demonstrated that ?-actin mRNA is associated with Htt, HAP1, and dynein intermediate chain in cultured neurons. Reduction in the levels of Htt, HAP1, KIF5A, and dynein heavy chain by lentiviral-based shRNAs resulted in a reduction in the transport of ?-actin mRNA. These findings support a role for Htt in participating in the mRNA transport machinery that also contains HAP1, KIF5A, and dynein.

SUBMITTER: Ma B

PROVIDER: S-EPMC3216621 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Huntingtin mediates dendritic transport of β-actin mRNA in rat neurons.

Ma Bin B Savas Jeffrey N JN Yu Man-Shan MS Culver Brady P BP Chao Moses V MV Tanese Naoko N

Scientific reports 20111103

Transport of mRNAs to diverse neuronal locations via RNA granules serves an important function in regulating protein synthesis within restricted sub-cellular domains. We recently detected the Huntington's disease protein huntingtin (Htt) in dendritic RNA granules; however, the functional significance of this localization is not known. Here we report that Htt and the huntingtin-associated protein 1 (HAP1) are co-localized with the microtubule motor proteins, the KIF5A kinesin and dynein, during d ...[more]

PMID: 22355657

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