title: Synaptic and nonsynaptic localization of protocadherin-gammaC5 in the rat brain.
abstract: It has been proposed that gamma-protocadherins (Pcdh-gammas) are involved in the establishment of specific patterns of neuronal connectivity. Contrary to the other Pcdh-gammas, which are expressed in the embryo, Pcdh-gammaC5 is expressed postnatally in the brain, coinciding with the peak of synaptogenesis. We have developed an antibody specific for Pcdh-gammaC5 to study the expression and localization of Pcdh-gammaC5 in brain. Pcdh-gammaC5 is highly expressed in the olfactory bulb, corpus striatum, dentate gyrus, CA1 region of the hippocampus, layers I and II of the cerebral cortex, and molecular layer of the cerebellum. Pcdh-gammaC5 is expressed in both neurons and astrocytes. In hippocampal neuronal cultures, and in the absence of astrocytes, a significant percentage of synapses, more GABAergic than glutamatergic, have associated Pcdh-gammaC5 clusters. Some GABAergic axons show Pcdh-gammaC5 in the majority of their synapses. Nevertheless, many Pcdh-gammaC5 clusters are not associated with synapses. In the brain, significant numbers of Pcdh-gammaC5 clusters are located at contact points between neurons and astrocytes. Electron microscopic immunocytochemistry of the rat brain shows that 1) Pcdh-gammaC5 is present in some GABAergic and glutamatergic synapses both pre- and postsynaptically; 2) Pcdh-gammaC5 is also extrasynaptically localized in membranes and in cytoplasmic organelles of neurons and astrocytes; and 3) Pcdh-gammaC5 is also localized in perisynaptic astrocyte processes. The results support the notions that 1) Pcdh-gammaC5 plays a role in synaptic specificity and/or synaptic maturation and 2) Pcdh-gammaC5 is involved in neuron-neuron synaptic interactions and in neuron-astrocyte interactions, including perisynaptic neuron-astrocyte interactions.
authors.affiliation: Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut 06269-3156, USA.
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Li
authors.forename: David R
authors.initials: DR
authors.lastname: Serwanski
authors.forename: Celia P
authors.initials: CP
authors.lastname: Miralles
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Fiondella
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Loturco
authors.forename: Maria E
authors.initials: ME
authors.lastname: Rubio
authors.forename: Angel L
authors.initials: AL
authors.lastname: De Blas
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000378:metabolism; D001921:Brain / Q000033:anatomy & histology* / Q000196:embryology / Q000254:growth & development / Q000378:metabolism*; D000070585:Cadherin Related Proteins; D015820:Cadherins / Q000378:metabolism*; D002478:Cells, Cultured; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D013569:Synapses / Q000378:metabolism* / Q000648:ultrastructure; D014018:Tissue Distribution; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D000070585:Cadherin Related Proteins; D015820:Cadherins; C464785:Gamma-protocadherins; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid