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bioRxiv · 10.1101/2020.09.05.283267

rab-27 acts in an intestinal secretory pathway to inhibit axon regeneration in C. elegans

Lin-Moore, A. T.·Oyeyemi, M. J.·Hammarlund, M.
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Abstract

Injured axons must regenerate to restore nervous system function, and regeneration is regulated in part by external factors from non-neuronal tissues. Many of these extrinsic factors act in the immediate cellular environment of the axon to promote or restrict regeneration, but the existence of long-distance signals regulating axon regeneration has not been clear. Here we show that the Rab GTPase rab-27 inhibits regeneration of GABAergic motor neurons in C. elegans through activity in the intestine. Re-expression of RAB-27, but not the closely related RAB-3, in the intestine of rab-27 mutant animals is sufficient to rescue normal regeneration. Several additional components of an intestinal neuropeptide secretion pathway also inhibit axon regeneration, including NPDC1/cab-1, SNAP25/aex-4, and KPC3/aex-5. Together these data indicate that RAB-27-dependent neuropeptide secretion from the intestine inhibits axon regeneration, and point to distal tissues as potent extrinsic regulators of regeneration.

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Lin-Moore, A. T., Oyeyemi, M. J., Hammarlund, M.. 2020-09-05. rab-27 acts in an intestinal secretory pathway to inhibit axon regeneration in C. elegans. https://doi.org/10.1101/2020.09.05.283267

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