Cplx3
Developmental stage
In the brain, expression starts at P6 and increases to reach a plateau at P20.
Function
Complexin that regulates SNARE protein complex-mediated synaptic vesicle fusion (PubMed:19386896). Required for the maintenance of synaptic ultrastructure in the adult retina (PubMed:19386896). Positively regulates synaptic transmission through synaptic vesicle availability and exocytosis of neurotransmitters at photoreceptor ribbon synapses in the retina (PubMed:15911881, PubMed:19386896, PubMed:27335398). Suppresses tonic photoreceptor activity and baseline 'noise' by suppression of Ca(2+) vesicle tonic release and the facilitation of evoked synchronous and asynchronous Ca(2+) vesicle release (PubMed:22694764, PubMed:27335398).
Post-translational modifications
Farnesylation mediates presynaptic targeting.
Sequence Similarities
Belongs to the complexin/synaphin family.
Tissue Specificity
Present in many brain regions, including hippocampus and cerebellum (at protein level) (PubMed:15911881). Expressed in the retina (at protein level) (PubMed:15911881, PubMed:19386896). Expressed in retinal amacrine cells (at protein level) (PubMed:19386896, PubMed:22694764). Expressed in retinal photoreceptor ribbon synapses (PubMed:19386896). Expressed in the retinal inner nuclear layer, at bipolar cells (at protein level) (PubMed:22694764). Expressed in cone photoreceptor synaptic terminals (at protein level) (PubMed:22694764).
Cellular localization
- Synapse
- Cell membrane
- Lipid-anchor
- Enriched at the synaptic terminal (PubMed:15911881). Localized at glycinergic synaptic contacts of AII amacrine cells with OFF cone bipolar cells in the OFF sublamina of the retina inner nuclear layer (PubMed:22694764).
Alternative names
Complexin-3, Complexin III, CPX III, Cplx3