Activation of Ras in neurons modifies synaptic vesicle docking and release.
We have recently demonstrated that constitutive activation of Ha-Ras in differentiated neurons induces structural remodeling of both axons and dendrites in a transgenic mouse model (referred as synRas mice). Here we show that this activation of neuronal Ras enhances docking of synaptic vesicles to active zones, thereby leading to an increase in the size of the readily releasable pool of vesicles, while the size of the total pool of synaptic vesicles remained unchanged. The morphological phenotype was associated with corresponding increases in the probability of glutamate release as revealed by changes in short-term synaptic plasticity. We, therefore, conclude that neuronal Ras activity contributes to the regulation of synaptic plasticity in adult mammalian brain at the presynaptic level.
Seeger
Gudrun
G
Paul Flechsig Institute for Brain Research, Department of Neuroanatomy, University Leipzig, D-04109 Leipzig, Germany.
Yan
Li
L
Gärtner
Ulrich
U
Huemmeke
Markus
M
Barmashenko
Gleb
G
Mittmann
Thomas
T
Heumann
Rolf
R
Arendt
Thomas
T
D000818:Animals; D000831:Animals, Newborn; D004558:Electric Stimulation / Q000379:methods; D004789:Enzyme Activation; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D051379:Mice; D008822:Mice, Transgenic; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D018408:Patch-Clamp Techniques / Q000379:methods; D011810:Quinoxalines / Q000494:pharmacology; D013003:Somatosensory Cortex / Q000166:cytology* / Q000502:physiology; D013569:Synapses / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D013572:Synaptic Vesicles / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D013997:Time Factors; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism*
D018691:Excitatory Amino Acid Antagonists; D011810:Quinoxalines; C056723:FG 9041; D018631:ras Proteins