Background

Ligands

Significance

Structure

Heterotrimeric G-Protein Structure

Novel Characteristics

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PIF/LLF Motif

DRY/ ERC Motif

MRGPRX2 has an rather than the typically conserved E/DRY Motif. The amino acid residue shift from TYR-174 to CYS-128 has spatial arrangement implications where the helices are more compact in MRGPRX2 without the TYR to physically push the TMP helices apart.

ERC Motif

Sodium Site

The MRGPRX2 consists of ASP-75 and GLY-116 compared to the previously conserved residues in this binding pocket. Other class A GPCRs demonstrate a larger binding pocket with a higher negative character allowing for a suitable environment for sodium ions to bind. In MRGPRX2, this pocket lacks the same negative character and the helices are more collapsed making this binding pocket less accessible for sodium ions.

Disulfide Bonds

Further Information

NPxxY Motif

The residue is pivotal for receptor activation in all Class A GPCRs.

Function

Before Activation

After Activation

Clinical Relevance

3D Structures

References