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BORC/kinesin-1 ensemble drives polarized transport of lysosomes into the axon.

ABSTRACT: The ability of lysosomes to move within the cytoplasm is important for many cellular functions. This ability is particularly critical in neurons, which comprise vast, highly differentiated domains such as the axon and dendrites. The mechanisms that control lysosome movement in these domains, however, remain poorly understood. Here we show that an ensemble of BORC, Arl8, SKIP, and kinesin-1, previously shown to mediate centrifugal transport of lysosomes in nonneuronal cells, specifically drives lysosome transport into the axon, and not the dendrites, in cultured rat hippocampal neurons. This transport is essential for maintenance of axonal growth-cone dynamics and autophagosome turnover. Our findings illustrate how a general mechanism for lysosome dispersal in nonneuronal cells is adapted to drive polarized transport in neurons, and emphasize the importance of this mechanism for critical axonal processes.

SUBMITTER: Farias GG

PROVIDER: S-EPMC5389300 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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BORC/kinesin-1 ensemble drives polarized transport of lysosomes into the axon.

Farías Ginny G GG Guardia Carlos M CM De Pace Raffaella R Britt Dylan J DJ Bonifacino Juan S JS

Proceedings of the National Academy of Sciences of the United States of America 20170320 14

The ability of lysosomes to move within the cytoplasm is important for many cellular functions. This ability is particularly critical in neurons, which comprise vast, highly differentiated domains such as the axon and dendrites. The mechanisms that control lysosome movement in these domains, however, remain poorly understood. Here we show that an ensemble of BORC, Arl8, SKIP, and kinesin-1, previously shown to mediate centrifugal transport of lysosomes in nonneuronal cells, specifically drives l ...[more]

PMID: 28320970

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