Neuroscience 2003 Abstract
| Presentation Number: | 691.3 |
|---|---|
| Abstract Title: | Identification of two proteins involved in astrocyte-induced synaptogenesis. |
| Authors: |
Christopherson, K. S.*1
; Ullian, E. M.1
; Mullowney, C.1
; Stokes, C.1
; Barres, B. A.1
1NeuroBiol., Stanford Med. Sch., 94305-5125, CA |
| Primary Theme and Topics |
Synaptic Transmission and Excitability - Glia -- Other |
| Session: |
691. Synaptic Transmission and Excitability: Glia II Poster |
| Presentation Time: | Tuesday, November 11, 2003 3:00 PM-4:00 PM |
| Location: | Morial Convention Center - Hall F-I, Board # D85 |
| Keywords: | SYNAPTOGENESIS, RETINAL GANGLION CELL, GLIA, SYNAPTIC TRANSMISSION |
What signals control synaptogenesis? We have previously demonstrated that astrocytes secrete a factor that increases the number of synapses on purified CNS neurons 7-fold (Science 2001 Jan 26:657-61). We have now identified two proteins that may play a crucial role in this process. First, we have identified a secreted molecule synthesized by astrocytes that is sufficient to induce structural synaptogenesis in vitro as assessed by immunocytochemistry and electron microscopy. This factor increases synapse number in a dose-dependent manner. Immunodepletion of this factor significantly reduces the synapse-promoting activity of ACM, indicating that this protein is necessary for the synapse-promoting activity and that extrinsic, astrocyte-derived proteins are able to regulate synapse number on neurons. We are currently identifying the receptor for this protein. Surprisingly, this protein is not sufficient to induce electrically active synapses (Ullian et. al., SFN 2003 abstract). Second, we have found an additional protein that is highly upregulated in neurons in response to soluble astrocyte signals that is also sufficient to induce structural synaptogenesis in vitro. Both molecules are localized to developing synapses throughout the brain in a temporally correlated manner. Future studies will determine whether these two molecules are part of the same pathway and identify the additional signals provided by astrocytes that regulate synaptic function. These studies identify the first known proteins sufficient to trigger formation of structural synapses between CNS neurons, and provide evidence that astrocytes may control synaptogenesis throughout the developing brain.
Supported by R01 NIDA (BA Barres), NEI NRSA (KS Christopherson) and a Zaffaroni fellowship (EM Ullian).
Sample Citation:
[Authors]. [Abstract Title]. Program No. XXX.XX. 2003 Neuroscience Meeting Planner. New Orleans, LA: Society for Neuroscience, 2003. Online.
Copyright © 2003-2025 Society for Neuroscience; all rights reserved. Permission to republish any abstract or part of any abstract in any form must be obtained in writing by SfN office prior to publication.
