Molecular architecture of glycinergic synapses.
Synapses can be considered chemical machines, which are optimized for fast and repeated exocytosis of neurotransmitters from presynaptic nerve terminals and the reliable electrical or chemical transduction of neurotransmitter binding to the appropriate receptors in the postsynaptic membrane. Therefore, synapses share a common repertoire of proteins like, e.g., the release machinery and certain cell adhesion molecules. This basic repertoire must be extended in order to generate specificity of neurotransmission and allow plastic changes, which are considered the basis of developmental and/or learning processes. Here, we focus on these complementary molecules located in the presynaptic terminal and postsynaptic membrane specializations of glycinergic synapses. Moreover, as specificity of neurotransmission in this system is established by the specific binding of the neurotransmitter to its receptor, we review the molecular properties of glycine receptor subunits and their assembly into functional glycine receptors with different functional characteristics. The past years have revealed that the molecular machinery underlying inhibitory and especially glycinergic postsynaptic membrane specializations is more complex and dynamic than previously anticipated from morphological studies. The emerging features include structural components as well as signaling modules, which could confer the plasticity required for the proper function of distinct motor and sensory functions.
Dresbach
Thomas
T
Department of Medical Cell Biology, Institute for Anatomy and Cell Biology, University of Heidelberg, Im Neuenheimer Feld 307, 69120 Heidelberg, Germany.
Nawrotzki
Ralph
R
Kremer
Thomas
T
Schumacher
Stefanie
S
Quinones
Daniel
D
Kluska
Martin
M
Kuhse
Jochen
J
Kirsch
Joachim
J
D000818:Animals; D001665:Binding Sites; D005998:Glycine / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D008024:Ligands; D008959:Models, Neurological; D017729:Presynaptic Terminals / Q000378:metabolism; D018009:Receptors, Glycine / Q000037:antagonists & inhibitors / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013569:Synapses / Q000187:drug effects / Q000378:metabolism*; D013570:Synaptic Membranes / Q000187:drug effects / Q000378:metabolism
D008024:Ligands; D018009:Receptors, Glycine; D005998:Glycine