Role of calcium dependant adenylate cyclase AC1 in the organization of corticospinal projections

Abstract

Event Abstract Back to Event Role of calcium dependant adenylate cyclase AC1 in the organization of corticospinal projections Hanane N. Ali1, Patricia Gaspar2 and Mohamed Bennis1* 1 Universite Cadi Ayyad, Laboratoire de Pharmacologie, Neurobiologie et Comportement, Faculte des Sciences, Morocco 2 Institut du Fer-a-Moulin, INSERM, U839, France Several guidance molecules are known to be involved at various decision points to regulate the projection of corticospinal axons. However, previous analyses of the corticospinal tract (CST) guidance defects in mutant mice lacking these molecules have suggested that there are other molecules involved in CST axon guidance that are yet to be identified. In this study, we investigate the role of cAMP signalling in the projection of motor CST axons in wild type and knockout-AC1 mice. To do so, we used in our study two different tracers: biotinylated Dextran amin (BDA) anterograde tracing of the motor CST axons and Fluorogold (FG) retrograde tracer to quantify the density of CST ipsilateral and controlateral projections on transverse sections at the level of high (C2-C4) and low cervical spinal cord (C5-C8). Our anterograde tracers show that in the controls mice, in the cervical spinal cord, many axons branched out from the crossed CST (main tract) in the dorsal and ventral horn. Some of these axons crossed to the ipsilateral grey matter. CST axons branch toward the lateral and ventral white matter. In knockout-AC1 mice, no differences were seen in the general distribution of ipsilateral as well as controlateral corticospinal terminal projections. Precise injection sites will more precisely reflecting the topographic plan of these projections in spinal cord (work in progress). Interestingly the result of our retrograde tracing did not show a similar phenotype of labelled motor neurons in the cortex between controls and knockout-AC1 mice. It could be that in vivo, the involvement of AC1 in the topographic organization of corticospinal tract is subtle, in contrast to what it has been shown for retinotectale and retinogeniculate systems. Although many questions remain, it is possible that other calcium-stimulated ACs, such as AC8, which is also expressed in the motor cortex, could be strongly involved in the organisation of these projections. It is evident that cAMP occupies a strategic position to control neuronal responses to a large variety of developmental cues that are important to investigate in the corticospinal tract axons in vitro. Conference: 3rd Mediterranean Conference of Neuroscience , Alexandria, Egypt, 13 Dec - 16 Dec, 2009. Presentation Type: Poster Presentation Citation: Ali HN, Gaspar P and Bennis M (2009). Role of calcium dependant adenylate cyclase AC1 in the organization of corticospinal projections. Front. Neurosci. Conference Abstract: 3rd Mediterranean Conference of Neuroscience . doi: 10.3389/conf.neuro.01.2009.16.171 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 26 Nov 2009; Published Online: 26 Nov 2009. * Correspondence: Mohamed Bennis, Universite Cadi Ayyad, Laboratoire de Pharmacologie, Neurobiologie et Comportement, Faculte des Sciences, Avenue My Abdellah, B.P. 2390, Marrakech, Morocco, mbennis@ucam.ac.ma Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Hanane N Ali Patricia Gaspar Mohamed Bennis Google Hanane N Ali Patricia Gaspar Mohamed Bennis Google Scholar Hanane N Ali Patricia Gaspar Mohamed Bennis PubMed Hanane N Ali Patricia Gaspar Mohamed Bennis Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.