| Annotated protein: | Calmodulin-3. Gene symbol: CALM3. Taxonomy: Rattus norvegicus (Rat). Uniprot ID: P0DP31 |
| antibody wiki: | |
| SynGO gene info: | SynGO data @ CALM3 |
| Ontology domain: | Cellular Component |
| SynGO term: | postsynaptic cytosol (GO:0099524) |
| Synapse type(s): | Schaffer collateral synapse (CA3->CA1) |
| Annotated paper: | Zhong L, et al. "Neurogranin targets calmodulin and lowers the threshold for the induction of long-term potentiation" PLoS One. 2012;7(7):e41275 PMID:22848456 |
| Figure(s): | 1A-B, 3C-D |
| Annotation description: | Immunogold labelling identified Calmodulin in both the pre and postsynaptic compartment. In addition, a further quantitative analysis of immunogold identified a selective accumulation of Calmodulin immunoreactivity underneath the morphologically defined postsynaptic density. As the CALM 1-3 genes are expressed in the hippocampus, these pools of synaptic calmodulin could derive from any or all of the CALM genes. |
| Evidence tracking, Biological System: | Cultured neurons |
| Evidence tracking, Protein Targeting: | Antibody (detection) |
| Evidence tracking, Experiment Assay: | Electron Microscopy |
| Non-tracable Author Statement (NAS): | This annotation required some inference over additional information/literature, and is not solely based on observations made in the annotated paper by its original authors. |
| Annotator(s): | Vincent O'Connor (ORCID:0000-0003-3185-5709) |
| Lab: | Biological Sciences, Institute for Life Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom |
| Additional literature: | pattern of expression of the three calmodulin (CaM) genes by in situ hybridization. Table 1 shows calmodulin 1, 2 and 3 mRNAs were expressed ubiquitously throughout the rat brain, albeit at varying expression levels. "Certain areas in the brain are highly laminated, in which layers containing neuronal perikarya, layers composed of mainly dendrites and their presynaptic afferents, or virtually exclusively axonal tracts, can be distinguished. Layers containing cell bodies, such as cerebral cortical Layers 2-6 (Figures 6A-6F), the cere- bellar granular and Purkinje cell layers (Figures 9A- 9F), the pyramidal cell layer of the hippocampus (Fig- ures 7A-7F), and the granular and mitral cell layers of the olfactory bulb (Figures 5A-5C), exhibited very strong expression for all three CaM genes (Table 1)." @ PMID:10219052 This data measures Calmodulin content in 5 major regions microdissected from rodent the brain. Striatum, cortex, cerebellum, diencephalon, medulla and pons. Whole fractionated homogenates allow assay of the abundance of Calmodulin immunoreactivity in synaptosomes. This evidences pools of synaptic calmodulin across synaptosomes from all regions of the brain. This annotation highlighting pools of synaptic calmodulin is confounded by the fact that calmodulin is encoded by 3 non-allelic genes (CALM-1, CALM-2, CALM-3) with identical protein sequence. Available mRNA expression data implies (see additional literature) that the calmodulin protein identified by protein chemical methods could have been derived from any of these genes. This cautions against ascribing synaptic calmodulin to an individual gene without additional evidence. Evidence that is largely lacking in the literature. @ PMID:3940289 immunoEM shows calmodulin expression in postsynaptic densities of Purkinje cells @ PMID:6355894 calmodulin is detected in synaptosomal fractions by mass-spectrometry @ PMID:33376223 calmodulin is detected in PSD fractions by mass-spectrometry @ PMID:28261056 immunofluorescence microscopy shows presynaptic calmodulin at retinal ribbon synapses @ PMID:33293457 Calm3 mRNA dendritic expression @ PMID:28765142 Calm1 mRNA somatic and dendritic expression @ PMID:33404500 Calm1 mRNA axonal expression @ PMID:31825308 Calm1 mRNA axonal expression @ PMID:26711345 This paper utilizes optimized radiolabelled mRNA probes for that specifically recognize (Figure1) each of the three calmodulin genes. There is a gross overlap in their expression but selective and differential expression based on quantification of discrete signals. This supports the notion that without additional experiment it is not possible to ascribe which of the CALM genes is responsible for the pools of synaptic calmodulin in the brain. @ PMID:12269397 |
| SynGO annotation ID: | 4715 |
| Dataset release (version): | 20231201 |
| View annotation as GO-CAM model: |  |