A role for zinc in postsynaptic density asSAMbly and plasticity?
Chemical synapses are asymmetric cell junctions that mediate communication between neurons. Multidomain scaffolding proteins of the Shank family act as major organizing elements of the "postsynaptic density"--that is, the cytoskeletal protein matrix associated with the postsynaptic membrane. A recent study has shown that the C-terminal sterile alpha-motif or "SAM domain" of Shank3 (also known as ProSAP2) can form two-dimensional sheets of helical fibers. Assembly and packaging of these fibers are markedly enhanced by the presence of Zn2+ ions. Zn2+ can be released together with glutamate from synaptic vesicles and can enter the postsynaptic cell through specific ionotropic receptors. Based on these observations, we propose a new model of synaptic plasticity in which Zn2+ influx directly and instantly modulates the structure and function of the postsynaptic density.
Gundelfinger
Eckart D
ED
Department of Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology, Brenneckestrasse 6, 39118 Magdeburg, Germany. gundelfinger@ifn-magdeburg.de
Boeckers
Tobias M
TM
Baron
Marisa K
MK
Bowie
James U
JU
D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry / Q000502:physiology*; D000818:Animals; D008959:Models, Neurological; D009419:Nerve Tissue Proteins; D009473:Neuronal Plasticity / Q000187:drug effects* / Q000502:physiology; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013569:Synapses / Q000737:chemistry / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology; D015032:Zinc / Q000502:physiology*
D048868:Adaptor Proteins, Signal Transducing; D009419:Nerve Tissue Proteins; C120532:Shank3 protein, rat; D015032:Zinc