Figure 1. Schematic representation of SchgrETHR and SchgrETH precursor.

(A) SchgrETHR is a rhodopsin-like GPCR with seven transmembrane regions. The highly conserved disulphide bridge, formed between a cystein (C) at the beginning of transmembrane 3 and in extracellular loop 2, is indicated in black. Following residues are accentuated: the histidine (H) typically conserved in transmembrane region 3 of all ETH receptors, the typical rhodopsin-like conserved ERY motif immediately following the third transmembrane helix and the leucine (L) replacing tryptophan (W), which is a typical feature of ETH receptors, in the highly conserved FXXCLXPFHXXR motif in transmembrane 6. (B) The AA sequence of two SchgrETH peptides are boxed, red residues differ between both peptides. Cleavage sites are indicated with arrows, while the signal peptide is emphasized by a thicker light blue line.