Naturally Occurring Polymorphisms of the Mouse Gammaretrovirus Receptors CAT-1 and XPR1 Alter Virus Tropism and Pathogenicity

Figure 4

Alignment of the predicted amino acid sequences of the N-terminal portion of the Env sequences of various XP-MLVs. Included are the prototype NZB-9-1 X-MLV, the Friend FrMCF P-MLV, the wild mouse isolates CasE#1 and Cz524, and XMRV. Green blocks identify the three variable domains of the RBD and the PRD, and a blue block identifies two residues that influence species tropism [93].