%0 Generic
%A Pilpel, Noam
%D 2009
%F heidok:9308
%K Protocadherins , AAV
%R 10.11588/heidok.00009308
%T Biochemical and Functional Analysis of gamma-Protocadherin Intracellular Signaling Pathways
%U https://archiv.ub.uni-heidelberg.de/volltextserver/9308/
%X The precisely organized complexity of the central nervous system (CNS) requires an enormous number of specific cell-cell interactions, presumably mediated by a diverse array of membrane associated proteins. The classic cadherins are known to play essential roles in the maintenance of neuronal connectivity and synaptic plasticity. Three complex genomic loci encoding proteins of the cadherin superfamily, the -, -, and - clustered protocadherins (Pcdhs), have been hypothesized to take part in this task. Their large number, diverse expression pattern during neurogenesis, and partial synaptic localization suggest a role in synaptogenesis. The genomic architecture of the clustered Pcdhs is reminiscent of the immunoglobulin and T-cell receptor clusters which confer the huge variety of antibody molecules: within each cluster, exons encoding variable extracellular and transmembrane domains are alternatively spliced onto a cluster-specific conserved intracellular domain. Thus, Pcdhs confer molecular diversity on the cell surface, with conserved signaling mechanisms in the cytoplasm. However, the physiological role of Pcdhs as well as the reason for the diversity of extracellular domains and the conservation of the intracellular domain have remained elusive. Our goal was the elucidation of the signal transduction pathways downstream of -Pcdh. To this end, we attempted to identify proteins that interact with the conserved intracellular domain of -Pcdhs (-ICD). We purified specific polyclonal antibodies targeted against the -ICD, and used them to immunoprecipitate interacting proteins from mouse forebrain lysates. Mass spectrometry analysis and subsequent co-immunoprecipitation identified novel proteins involved in signal transduction pathways related to cell cycle control, synaptic plasticity and memory formation. To study the role of -Pcdh intracellular signaling in vivo, we additionally established a viral gene-delivery system into neonatal (P0) mouse brains. This method enabled us to efficiently overexpress the -ICD, which allowed us to study the intracellular signaling of -Pcdhs. Using this system we uncovered novel physiological effects of -ICD overexpression in inhibitory synapses of the cortex, with possible implications for synaptic transmission and plasticity.