The Examination of Autotaxin in the Production of LPA as an Axon Guidance Molecule in Chicken Retinal Ganglion Cells
Poster Number
05
College
College of Arts and Sciences
Keywords
Brain, Development, Visual System, Neuroscience
Department
Biology
Faculty Mentor
Dr. Eric Birgbauer
Abstract
Growth cones direct axon pathfinding during neurological development. The finger-like projections do this by detecting environmental stimuli, which are referred to as axon guidance molecules. Lysophosphatidic acid (LPA) is produced by the enzyme autotaxin (ATX) and has been demonstrated to cause growth cone collapse in vitro. ATX has been found in the mid-forebrain boundary of the embryonic chick brain, a target region for retinal axons. To understand LPA’s role in axon guidance, we injected a virus expressing an siRNA agent for ATX into chick brains prior to retinal axon innervation at day three of development (E3), and then examined retinal axon guidance to the target, the optic tectum, at E12. Through viral expression of the siRNA, the mRNA transcript of ATX is silenced, thereby depleting the production of enzyme and its subsequent product, LPA. Using a control virus that does not silence ATX, and thus not inhibit LPA production, preliminary data demonstrate normal retinal axon development and pathfinding to the optic tectum. Examination of optic tecti with the ATX/siRNA virus under fluorescence and confocal microscopy will allow us to investigate whether LPA acts as an axon guidance molecule for retinal axons at the tectum.
Previously Presented/Performed?
Symposium for Young Neurosciences and Professors of the Southeast (SYNAPSE), Presbyterian College, April 2016
Grant Support?
Supported by a grant from the National Eye Institute of the National Institutes of Health
Start Date
22-4-2016 12:00 PM
End Date
22-4-2016 2:00 PM
The Examination of Autotaxin in the Production of LPA as an Axon Guidance Molecule in Chicken Retinal Ganglion Cells
Rutledge
Growth cones direct axon pathfinding during neurological development. The finger-like projections do this by detecting environmental stimuli, which are referred to as axon guidance molecules. Lysophosphatidic acid (LPA) is produced by the enzyme autotaxin (ATX) and has been demonstrated to cause growth cone collapse in vitro. ATX has been found in the mid-forebrain boundary of the embryonic chick brain, a target region for retinal axons. To understand LPA’s role in axon guidance, we injected a virus expressing an siRNA agent for ATX into chick brains prior to retinal axon innervation at day three of development (E3), and then examined retinal axon guidance to the target, the optic tectum, at E12. Through viral expression of the siRNA, the mRNA transcript of ATX is silenced, thereby depleting the production of enzyme and its subsequent product, LPA. Using a control virus that does not silence ATX, and thus not inhibit LPA production, preliminary data demonstrate normal retinal axon development and pathfinding to the optic tectum. Examination of optic tecti with the ATX/siRNA virus under fluorescence and confocal microscopy will allow us to investigate whether LPA acts as an axon guidance molecule for retinal axons at the tectum.
