FIG. 5.

(A) Amino acid sequences encoded by the UL144 ORF and representing each of the three major groups of strains. CRDs from TNFR superfamily members HveA and variola G2R (3, 25, 44) are aligned to show homology (from a BLAST search [1]). Numbers correspond to amino acid residues of either the predicted UL144 product or the TNFR superfamily member identified by use of BLAST. Potential functional features associated with growth factor receptors are designated as follows: single line, signal peptide; double line, CRDs; shading, conserved cysteines; broken line, transmembrane domain; arrows, N glycosylation sites of UL144 sequences identified by use of PROSITE (2). (B) Identity of the UL144 group 3 sequence with various members of the TNFR superfamily (4). The percent identities in the ectodomains (without leader sequences) and CRD2 were calculated from the fraction of identical residues following pairwise alignment.