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Title: Diverse FGF receptor signaling controls astrocyte specification and proliferation

Abstract

During CNS development, pluripotency neuronal progenitor cells give rise in succession to neurons and glia. Fibroblast growth factor-2 (FGF-2), a major signal that maintains neural progenitors in the undifferentiated state, is also thought to influence the transition from neurogenesis to gliogenesis. Here we present evidence that FGF receptors and underlying signaling pathways transmit the FGF-2 signals that regulate astrocyte specification aside from its mitogenic activity. Application of FGF-2 to cortical progenitors suppressed neurogenesis whereas treatment with an FGFR antagonist in vitro promoted neurogenesis. Introduction of chimeric FGFRs with mutated tyrosine residues into cortical progenitors and drug treatments to specifically block individual downstream signaling pathways revealed that the overall activity of FGFR rather than individual autophosphorylation sites is important for delivering signals for glial specification. In contrast, a signal for cell proliferation by FGFR was mainly delivered by MAPK pathway. Together our findings indicate that FGFR activity promotes astrocyte specification in the developing CNS.

Authors:
 [1];  [1];  [2]
  1. School of Life Sciences, Gwangju Institute of Science and Technology, Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of)
  2. (Korea, Republic of)
Publication Date:
OSTI Identifier:
22202502
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 395; Journal Issue: 3; Other Information: Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; CELL PROLIFERATION; DRUGS; FIBROBLASTS; GROWTH FACTORS; IN VITRO; NERVE CELLS; RECEPTORS; RESIDUES; TYROSINE

Citation Formats

Kang, Kyungjun, Song, Mi-Ryoung, E-mail: msong@gist.ac.kr, and Bioimaging Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Oryong-dong, Buk-gu, Gwangju 500-712. Diverse FGF receptor signaling controls astrocyte specification and proliferation. United States: N. p., 2010. Web. doi:10.1016/J.BBRC.2010.03.174.
Kang, Kyungjun, Song, Mi-Ryoung, E-mail: msong@gist.ac.kr, & Bioimaging Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Oryong-dong, Buk-gu, Gwangju 500-712. Diverse FGF receptor signaling controls astrocyte specification and proliferation. United States. doi:10.1016/J.BBRC.2010.03.174.
Kang, Kyungjun, Song, Mi-Ryoung, E-mail: msong@gist.ac.kr, and Bioimaging Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Oryong-dong, Buk-gu, Gwangju 500-712. 2010. "Diverse FGF receptor signaling controls astrocyte specification and proliferation". United States. doi:10.1016/J.BBRC.2010.03.174.
@article{osti_22202502,
title = {Diverse FGF receptor signaling controls astrocyte specification and proliferation},
author = {Kang, Kyungjun and Song, Mi-Ryoung, E-mail: msong@gist.ac.kr and Bioimaging Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Oryong-dong, Buk-gu, Gwangju 500-712},
abstractNote = {During CNS development, pluripotency neuronal progenitor cells give rise in succession to neurons and glia. Fibroblast growth factor-2 (FGF-2), a major signal that maintains neural progenitors in the undifferentiated state, is also thought to influence the transition from neurogenesis to gliogenesis. Here we present evidence that FGF receptors and underlying signaling pathways transmit the FGF-2 signals that regulate astrocyte specification aside from its mitogenic activity. Application of FGF-2 to cortical progenitors suppressed neurogenesis whereas treatment with an FGFR antagonist in vitro promoted neurogenesis. Introduction of chimeric FGFRs with mutated tyrosine residues into cortical progenitors and drug treatments to specifically block individual downstream signaling pathways revealed that the overall activity of FGFR rather than individual autophosphorylation sites is important for delivering signals for glial specification. In contrast, a signal for cell proliferation by FGFR was mainly delivered by MAPK pathway. Together our findings indicate that FGFR activity promotes astrocyte specification in the developing CNS.},
doi = {10.1016/J.BBRC.2010.03.174},
journal = {Biochemical and Biophysical Research Communications},
number = 3,
volume = 395,
place = {United States},
year = 2010,
month = 5
}
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