Domain

Metabotropic glutamate receptor, Homer-binding domain (IPR019588)

Short name: Metabotropic_Glu_rcpt_Homer-bd

Domain relationships

None.

Description

This entry represents the proline-rich region of metabotropic glutamate receptor proteins that bind Homer-related synaptic proteins.

Metabotropic glutamate receptors function as receptors for glutamate. The activity of this receptor is mediated by a G-protein that activates a phosphatidylinositol-calcium second messenger system.

The Homer proteins form a physical tether linking mGluRs with the inositol trisphosphate receptors (IP3R) that appears to be due to the proline-rich Homer ligand (PPXXFr). Activation of PI turnover triggers intracellular calcium release [PMID: 9808459]. Metabotropic glutamate receptor (MGluR) function is altered in the mouse model of human Fragile X syndrome mental retardation, a disorder caused by loss of function mutations in the Fragile X mental retardation gene Fmr1. Homer 3 (and to a lesser extent Homer 1b/c) has been shown to form a multimeric complex with mGlu1a and the IP3 receptor, indicating that Homers may play a role in the localisation of receptors to their signalling partners [PMID: 18184796].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
Pfam
SMART