| Annotated protein: | Voltage-dependent calcium channel gamma-8 subunit (Neuronal voltage-gated calcium channel gamma-8 subunit) (Transmembrane AMPAR regulatory protein gamma-8) (TARP gamma-8). Gene symbol: CACNG8. Taxonomy: Mus musculus (Mouse). Uniprot ID: Q8VHW2 |
| antibody wiki: | |
| SynGO gene info: | SynGO data @ CACNG8 |
| Ontology domain: | Biological Process |
| SynGO term: | regulation of postsynaptic membrane neurotransmitter receptor levels (GO:0099072) |
| Synapse type(s): | hippocampus, glutamatergic Schaffer collateral synapse (CA3->CA1) |
| Annotated paper: | Fukaya M, et al. "Abundant distribution of TARP gamma-8 in synaptic and extrasynaptic surface of hippocampal neurons and its major role in AMPA receptor expression on spines and dendrites" Eur J Neurosci. 2006 Oct;24(8):2177-90 PMID:17074043 |
| Figure(s): | Figure 6, 7 |
| Annotation description: | TARP γ-8 regulates the number of synaptic and extrasynaptic AMPA receptors in dendrites and spines. Fig. 4: "In γ-8-KO mice, AMPA receptors were significantly reduced to half the level of control mice" Western blot analysis of PSD fractions from WT and KO hippocampal tissue showed a significant reduction in AMPAR protein in all KO fractions compared to WT (pan AMPAR anitbody, Fig. 4D-E). GluA2 and PSD95 protein levels were unchanged. Also showed validation of KO by Southern blot and immunoblot analysis. Fig. 5. "Marked decrease of AMPA receptor immunofluorescence in γ-8-knockout (KO) hippocampus" Decrease in AMPARs in the dendritic layers of CA1, CA3, and dentate gyrus (Fig. 5G-L). No difference were observed for NR1 or vGlut1 (Fig. 5C-F). "Severe deficits of surface AMPA receptors on spines and dendrites, but not somata, in γ-8-KO CA1 pyramidal cells" Fig. 6: Post-embedding immunogold labeling using a pan-AMPAR antibody that binds to extracellular epitopes on the receptor. Synaptic AMPARs at axo-spinous asymmetrical synapses in the CA1 and CA3 stratum radiatum were significantly reduced in γ-8 KO compared to WT (Fig. 6A-B, G, I) Fig 7: Pre-embedding silver-enhanced immunogold with a GluR1-antibody that recognizes intracellular epitopes was used to asses changes in extrasynaptic and intracellular AMPARs. Extrasynaptic GluA1 labeling in spines and dendritic shafts of pyramidal cells from γ-8-KO mice was significantly reduced compared to controls (37% and 36%, respectively, Fig. 7J). 22/2/2018 Pim - "Therefore, in CA1 pyramidal cells of γ-8-KO mice, extrasynaptic GluRα1 labeling in spines and dendrites are reduced severely and similarly to synaptic AMPA receptors (Fig. 6G)." |
| Evidence tracking, Biological System: | Intact tissue |
| Evidence tracking, Protein Targeting: | Genetic transformation (eg; knockout, knockin, mutations) |
| Evidence tracking, Experiment Assay: | Electron Microscopy |
| Annotator(s): | Hana Goldschmidt (ORCID:0000-0002-5676-366X) Richard Huganir (ORCID:0000-0001-9783-5183) |
| Lab: | Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA and Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD 21205, USA |
| Additional literature: | Figure 5- PSD prep shows TARPg8 localization in PSD fraction @ PMID:21172611 Figure 6A- PSD prep @ PMID:12771129 |
| SynGO annotation ID: | 2637 |
| Dataset release (version): | 20231201 |
| View annotation as GO-CAM model: |  |