|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
First published online 26 October 2004
doi: 10.1242/jcs.01511
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Research Article |
1 Institute of Physiology and Pathophysiology, Johannes Gutenberg-University Mainz, Duesbergweg 6, 55128 Mainz, Germany
2 Department of Molecular Neurobiochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
3 Institute for Clinical Neurobiology, Julius-Maximilians University Würzburg, Sanderring 2 - 97070 Würzburg, Germany
* Author for correspondence (e-mail: lessmann{at}uni-mainz.de)
Accepted 24 August 2004
The Trk family of receptor tyrosine kinases and the p75 receptor (p75NTR) mediate the effects of neurotrophins on neuronal survival, differentiation and synaptic plasticity. The neurotrophin BDNF and its cognate receptor tyrosine kinase, TrkB.FL, are highly expressed in neurons of the central nervous system. At later stages in postnatal development the truncated TrkB splice variants (TrkB.T1, TrkB.T2) become abundant. However, the signalling and function of these truncated receptors remained largely elusive.
We show that overexpression of TrkB.T1 in hippocampal neurons induces the formation of dendritic filopodia, which are known precursors of synaptic spines. The induction of filopodia by TrkB.T1 occurs independently of neurotrophin binding and of kinase activity of endogenous TrkB.FL. Coexpression of a p75NTR lacking an intracellular domain inhibits the TrkB.T1-induced effect in a dominant negative manner. Steric hindrance of extracellular p75NTR interactions with a specific antibody, or absence of p75NTR with an intact extracellular domain also inhibit this TrkB.T1-induced effect.
We thus propose a novel signalling pathway initiated by neurotrophin-independent extracellular or intramembrane interaction of TrkB.T1 with the p75NTR receptor, which modulates dendritic growth via p75NTR signalling cascades.
Key words: Neurotrophins, Trk, p75 receptor, Filopodia, BDNF, Spines
This article has been cited by other articles:
![]() |
M. G. Martin, S. Perga, L. Trovo, A. Rasola, P. Holm, T. Rantamaki, T. Harkany, E. Castren, F. Chiara, and C. G. Dotti Cholesterol Loss Enhances TrkB Signaling in Hippocampal Neurons Aging in Vitro Mol. Biol. Cell, May 1, 2008; 19(5): 2101 - 2112. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Singh, C. Henneberger, D. Betances, M. A. Arevalo, A. Rodriguez-Tebar, J. C. Meier, and R. Grantyn Altered balance of glutamatergic/GABAergic synaptic input and associated changes in dendrite morphology after BDNF expression in BDNF-deficient hippocampal neurons. J. Neurosci., July 5, 2006; 26(27): 7189 - 7200. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. De Wit, R. Eggers, R. Evers, E. Castren, and J. Verhaagen Long-Term Adeno-Associated Viral Vector-Mediated Expression of Truncated TrkB in the Adult Rat Facial Nucleus Results in Motor Neuron Degeneration J. Neurosci., February 1, 2006; 26(5): 1516 - 1530. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Chakravarthy, M. H. Saiepour, M. Bence, S. Perry, R. Hartman, J. J. Couey, H. D. Mansvelder, and C. N. Levelt Postsynaptic TrkB signaling has distinct roles in spine maintenance in adult visual cortex and hippocampus PNAS, January 24, 2006; 103(4): 1071 - 1076. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Zagrebelsky, A. Holz, G. Dechant, Y.-A. Barde, T. Bonhoeffer, and M. Korte The p75 Neurotrophin Receptor Negatively Modulates Dendrite Complexity and Spine Density in Hippocampal Neurons J. Neurosci., October 26, 2005; 25(43): 9989 - 9999. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. M. Mitrasinovic, A. Grattan, C. C. Robinson, N. B. Lapustea, C. Poon, H. Ryan, C. Phong, and G. M. Murphy Jr Microglia Overexpressing the Macrophage Colony-Stimulating Factor Receptor Are Neuroprotective in a Microglial-Hippocampal Organotypic Coculture System J. Neurosci., April 27, 2005; 25(17): 4442 - 4451. [Abstract] [Full Text] [PDF] |
||||