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bioRxiv · 10.1101/301275

Repulsive Guidance Molecule Acts in Axon Branching in Caenorhabditis elegans

Tsutsui, K.·Kim, H.-S.·Kubota, Y.·Shibata, Y.·Tian, C.·Liu, J.·Nishiwaki, K.
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Abstract

Repulsive guidance molecules (RGMs) are evolutionarily conserved proteins implicated in repulsive axon guidance. Here we report the function of the Caenorhabditis elegans ortholog DRAG-1 in axon branching. The axons of hermaphrodite-specific neurons (HSNs) branch at the region abutting the vulval muscles and innervate these muscles to control egg laying. The drag-1 mutants exhibited defects in HSN axon branching in addition to a small body size and egg laying-defective phenotype. DRAG-1 expression in the hypodermal cells was required for the branching of these axons. The C-terminal glycosylphosphatidylinositol anchor of DRAG-1 was important for its function. Genetic analyses suggested that the membrane receptor UNC-40, but neither SMA-1/{beta}H-spectrin nor SMA-5/MAP kinase 7, acts in the same pathway with DRAG-1 in HSN branching. We propose that DRAG-1 expressed in the hypodermis signals via the UNC-40 receptor expressed in HSNs to elicit branching activity of HSN axons.

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Tsutsui, K., Kim, H.-S., Kubota, Y., Shibata, Y., Tian, C., Liu, J., Nishiwaki, K.. 2018-04-16. Repulsive Guidance Molecule Acts in Axon Branching in Caenorhabditis elegans. https://doi.org/10.1101/301275

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