Wnt-7a modulates the synaptic vesicle cycle and synaptic transmission in hippocampal neurons.
Wnt signaling is essential for neuronal development and the maintenance of the developing nervous system. Recent studies indicated that Wnt signaling modulates long term potentiation in adult hippocampal slices. We report here that different Wnt ligands are present in hippocampal neurons of rat embryo and adult rat, including Wnt-4, -5a, -7a, and -11. Wnt-7a acts as a canonical Wnt ligand in rat hippocampal neurons, stimulates clustering of presynaptic proteins, and induces recycling and exocytosis of synaptic vesicles as studied by FM dyes. Wnt-3a has a moderate effect on recycling of synaptic vesicles, and no effect of Wnt-1 and Wnt-5a was detected. Electrophysiological analysis on adult rat hippocampal slices indicates that Wnt-7a, but not Wnt-5a, increases neurotransmitter release in CA3-CA1 synapses by decreasing paired pulse facilitation and increasing the miniature excitatory post-synaptic currents frequency. These results indicate that the presynaptic function of rat hippocampal neurons is modulated by the canonical Wnt signaling.
Cerpa
Waldo
W
Centro de Regulación Celular y Patología Joaquín V. Luco, Instituto Milenio MIFAB, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, P. Universidad Católica de Chile, Alameda 340, 8331010 Santiago, Chile
Godoy
Juan A
JA
Alfaro
Iván
I
Farías
Ginny G
GG
Metcalfe
María J
MJ
Fuentealba
Rodrigo
R
Bonansco
Christian
C
Inestrosa
Nibaldo C
NC
D000375:Aging / Q000502:physiology; D000818:Animals; D002460:Cell Line; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism*; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D017774:Long-Term Potentiation / Q000502:physiology*; D042282:Microdissection; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D017729:Presynaptic Terminals / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013572:Synaptic Vesicles / Q000378:metabolism*; D051153:Wnt Proteins / Q000378:metabolism*
D011518:Proto-Oncogene Proteins; D051153:Wnt Proteins; C490507:Wnt7a protein, rat