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A Neuronal piRNA Pathway Inhibits Axon Regeneration in C. elegans.

ABSTRACT: The PIWI-interacting RNA (piRNA) pathway has long been thought to function solely in the germline, but evidence for its functions in somatic cells is emerging. Here we report an unexpected role for the piRNA pathway in Caenorhabditis elegans sensory axon regeneration after injury. Loss of function in a subset of components of the piRNA pathway results in enhanced axon regrowth. Two essential piRNA factors, PRDE-1 and PRG-1/PIWI, inhibit axon regeneration in a gonad-independent and cell-autonomous manner. By smFISH analysis we find that prde-1 transcripts are present in neurons, as well as germ cells. The piRNA pathway inhibits axon regrowth independent of nuclear transcriptional silencing but dependent on the slicer domain of PRG-1/PIWI, suggesting that post-transcriptional gene silencing is involved. Our results reveal the neuronal piRNA pathway as a novel intrinsic repressor of axon regeneration.

SUBMITTER: Kim KW

PROVIDER: S-EPMC5866297 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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A Neuronal piRNA Pathway Inhibits Axon Regeneration in C. elegans.

Kim Kyung Won KW Tang Ngang Heok NH Andrusiak Matthew G MG Wu Zilu Z Chisholm Andrew D AD Jin Yishi Y

Neuron 20180127 3

The PIWI-interacting RNA (piRNA) pathway has long been thought to function solely in the germline, but evidence for its functions in somatic cells is emerging. Here we report an unexpected role for the piRNA pathway in Caenorhabditis elegans sensory axon regeneration after injury. Loss of function in a subset of components of the piRNA pathway results in enhanced axon regrowth. Two essential piRNA factors, PRDE-1 and PRG-1/PIWI, inhibit axon regeneration in a gonad-independent and cell-autonomou ...[more]

PMID: 29395906

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