Publication Date:
2015-09-04
Description:
by John A. Gaynes, Hideo Otsuna, Douglas S. Campbell, John P. Manfredi, Edward M. Levine, Chi-Bin Chien Attractive growth cone turning requires Igf2bp1-dependent local translation of β-actin mRNA in response to external cues in vitro . While in vivo studies have shown that Igf2bp1 is required for cell migration and axon terminal branching, a requirement for Igf2bp1 function during axon outgrowth has not been demonstrated. Using a timelapse assay in the zebrafish retinotectal system, we demonstrate that the β-actin 3’UTR is sufficient to target local translation of the photoconvertible fluorescent protein Kaede in growth cones of pathfinding retinal ganglion cells (RGCs) in vivo . Igf2bp1 knockdown reduced RGC axonal outgrowth and tectal coverage and retinal cell survival. RGC-specific expression of a phosphomimetic Igf2bp1 reduced the density of axonal projections in the optic tract while sparing RGCs, demonstrating for the first time that Igf2bp1 is required during axon outgrowth in vivo . Therefore, regulation of local translation mediated by Igf2bp proteins may be required at all stages of axon development.
Electronic ISSN:
1932-6203
Topics:
Medicine
,
Natural Sciences in General
