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Frazzled promotes growth cone attachment at the source of a Netrin gradient in the Drosophila visual system.

ABSTRACT: Axon guidance is proposed to act through a combination of long- and short-range attractive and repulsive cues. The ligand-receptor pair, Netrin (Net) and Frazzled (Fra) (DCC, Deleted in Colorectal Cancer, in vertebrates), is recognized as the prototypical effector of chemoattraction, with roles in both long- and short-range guidance. In the Drosophila visual system, R8 photoreceptor growth cones were shown to require Net-Fra to reach their target, the peak of a Net gradient. Using live imaging, we show, however, that R8 growth cones reach and recognize their target without Net, Fra, or Trim9, a conserved binding partner of Fra, but do not remain attached to it. Thus, despite the graded ligand distribution along the guidance path, Net-Fra is not used for chemoattraction. Based on findings in other systems, we propose that adhesion to substrate-bound Net underlies both long- and short-range Net-Fra-dependent guidance in vivo, thereby eroding the distinction between them.

SUBMITTER: Akin O

PROVIDER: S-EPMC5108592 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Frazzled promotes growth cone attachment at the source of a Netrin gradient in the <i>Drosophila</i> visual system.

Akin Orkun O Zipursky S Lawrence SL

eLife 20161015

Axon guidance is proposed to act through a combination of long- and short-range attractive and repulsive cues. The ligand-receptor pair, Netrin (Net) and Frazzled (Fra) (DCC, Deleted in Colorectal Cancer, in vertebrates), is recognized as the prototypical effector of chemoattraction, with roles in both long- and short-range guidance. In the <i>Drosophila</i> visual system, R8 photoreceptor growth cones were shown to require Net-Fra to reach their target, the peak of a Net gradient. Using live im ...[more]

PMID: 27743477

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The Drosophila Netrin receptor frazzled/DCC functions as an invasive tumor suppressor.

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