E/DRY motif

One of the more striking elements of sequence conservation is the Glu/ Asp-Arg-Tyr sequence found at the cytoplasmic interface of TM III (Fig. 5). This so-called (E/DRY) motif is actually E-R-Y in... 

It is not yet known whether other conserved functional motifs characteristic of class A GPCRs are involved in C5a receptor activation. The E/DRY motif, actually DRF in this receptor (Fig. 6), has not yet been investigated. Similarly, the conserved Pro of the TXP motif, ALP in this receptor (Fig. 6), could be involved in receptor activation but this possibility has not been examined. More generally, while some conserved Pro residues may play a role in activation, they have long been proposed to be important for normal receptor folding and membrane insertion (Kolakowski et al., 1995). 

---