Stability of dendritic spines and synaptic contacts is controlled by alpha N-catenin.
Morphological plasticity of dendritic spines and synapses is thought to be crucial for their physiological functions. Here we show that alpha N-catenin, a linker between cadherin adhesion receptors and the actin cytoskeleton, is essential for stabilizing dendritic spines in rodent hippocampal neurons in culture. In the absence of alpha N-catenin, spine heads were abnormally motile, actively protruding filopodia from their synaptic contact sites. Conversely, alpha N-catenin overexpression in dendrites reduced spine turnover, causing an increase in spine and synapse density. Tetrodotoxin (TTX), a neural activity blocker, suppressed the synaptic accumulation of alpha N-catenin, whereas bicuculline, a GABA antagonist, promoted it. Furthermore, excess alpha N-catenin rendered spines resistant to the TTX treatment. These results suggest that alpha N-catenin is a key regulator for the stability of synaptic contacts.
Abe
Kentaro
K
RIKEN Center for Developmental Biology, 2-2-3 Minatojima-Minamimachi, Chuo-ku, Kobe 650-0047, Japan.
Chisaka
Osamu
O
Van Roy
Frans
F
Takeichi
Masatoshi
M
D000818:Animals; D015820:Cadherins / Q000502:physiology; D003598:Cytoskeletal Proteins / Q000502:physiology*; D003712:Dendrites / Q000378:metabolism*; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism; D066298:In Vitro Techniques; D051379:Mice; D008817:Mice, Mutant Strains; D009419:Nerve Tissue Proteins / Q000502:physiology*; D016501:Neurites / Q000378:metabolism; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013569:Synapses / Q000378:metabolism*; D051178:alpha Catenin
D015820:Cadherins; C486820:Ctnna2 protein, mouse; D003598:Cytoskeletal Proteins; D009419:Nerve Tissue Proteins; D051178:alpha Catenin