Structural Diversity in Conserved Regions Like the DRY-Motif among Viral 7TM Receptors—A Consequence of Evolutionary Pressure?

Figure 1

Phylogenetic tree of viral and human chemokine receptors based on their amino acid sequence. The length of each branch reflects the similarity between receptors. It was generated by aligning the sequences using the settings: Blosum62, gap open penalty of 5 and gap extension penalty of 0.1 followed by the Jukes-Cantor distance analysis done in Geneious Pro. For further information about the virus-encoded receptors and GenBank accession number please see Table 1. *As the sequence of these viral receptors are very alike it cannot be excluded that they are in fact the same.