The domain within your query sequence starts at position 1 and ends at position 47; the E-value for the Calcyon domain shown below is 7.5e-19.



PFAM accession number:PF06387
Interpro abstract (IPR009431):

This family includes the neuron-enriched endosomal proteins NSG1 (NEEP21), NSG2 (P19) and NSG3 (calcyon, Caly). They interact with distinct elements of the endosomal and synaptic scaffolding machinery [ (PUBMED:25376768) ]. NSG1 and NSG2 may not be resident endosomal proteins, and are also known as neuronal vesicle trafficking-associated proteins 1 and 2 respectively [ (PUBMED:28874679) ]. NSG1/NEEP21 plays a role in the trafficking of multiple receptors, including the cell adhesion molecule L1/NgCAM, the neurotransmitter receptor GluA2, and beta-APP [ (PUBMED:28299779) ]. The role of NSG2 is not known.

It was originally thought that the Neuron-specific vesicular protein calcyon (previously known as D1 dopamine receptor-interacting, calcyon), interacted directly with the D1 dopamine receptor (DRD1) to modulate neocortical and hippocampal neuronal excitability [ (PUBMED:10698743) ] as well as cAMP-dependent signalling [ (PUBMED:11929934) ]. However, this work was retracted, as it was shown that a direct interaction with the dopamine D1 receptor had been misinterpreted [ (PUBMED:17170272) ]. However, it has been shown that calcyon induces D1DR to stimulate intracellular Ca2+ release, and this suggests a possible functional interaction between calcyon and D1DR, despite there being, as yet, no direct interaction between them. A recent study suggested that calcyon-containing vesicles might transport D1DR by associating calcyon with D1DR through their assembly to clathrin [ (PUBMED:16595675) ]. However, as a single transmembrane protein, it is currently not clear how calcyon can regulate the internalization of D1DR from the plasma membrane to endocytic vesicles.

Calcyon is a brain-specific protein, mainly localized in the intracellular endosomal vesicles of dendritic spines in dopamine expressing pyramidal cells in the prefrontal cortex and hippocampus and dorsal striatum region [ (PUBMED:11929934) (PUBMED:10698743) ]. Neuron-specific vesicular protein calcyon has implicated in clathrin-mediated endocytosis. It is exclusively expressed in neurons, and localized in moving vesicles and it thought to play a role in brain plasticity [ (PUBMED:17885599) ]. Defective calcyon proteins have been implicated in both attention-deficit/hyperactivity disorder (ADHD) [ (PUBMED:11923911) (PUBMED:17623072) ] and schizophrenia [ (PUBMED:12622665) ].

GO process:dopamine receptor signaling pathway (GO:0007212), clathrin coat assembly (GO:0048268)
GO component:integral component of membrane (GO:0016021)
GO function:clathrin light chain binding (GO:0032051)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry Calcyon