Structural Diversity in Conserved Regions Like the DRY-Motif among Viral 7TM Receptors-A Consequence of Evolutionary Pressure?
Several herpes- and poxviruses have captured chemokine receptors from their hosts and modified these to their own benefit. The human and viral chemokine receptors belong to class A 7 transmembrane (TM) receptors which are characterized by several structural motifs like the DRY-motif in TM3 and the C-terminal tail. In the DRY-motif, the arginine residue serves important purposes by being directly involved in G protein coupling. Interestingly, among the viral receptors there is a greater diversity in the DRY-motif compared to their endogenous receptor homologous. The C-terminal receptor tail constitutes another regulatory region that through a number of phosphorylation sites is involved in signaling, desensitization, and internalization. Also this region is more variable among virus-encoded 7TM receptors compared to human class A receptors. In this review we will focus on these two structural motifs and discuss their role in viral 7TM receptor signaling compared to their endogenous counterparts.
Laboratory for Molecular Pharmacology, Department of Neuroscience and Pharmacology, The Panum Institute, University of Copenhagen, Building 18.5, Blegdamsvej 3, 2200-Copenhagen N, Denmark.
Ann-Sofie Mølleskov
AS
Jensen
Alexander Hovard
AH
Sparre-Ulrich
Nicholas
N
Davis-Poynter
Mette Marie
MM
Rosenkilde