Patent ID: 8557971

Claim:
A polynucleotide encoding a chimeric viral envelope polypeptide comprising: a first polypeptide into which a second polypeptide is inserted at an insertion point; wherein the first polypeptide sequence, prior to the insertion of said second polypeptide, consists of the polypeptide sequence of a murine or feline leukemia virus envelope polypeptide whose amino acid sequence is at least 70% identical to SEQ ID NO:2; wherein the second polypeptide sequence consists of a receptor-binding domain of a second, different viral envelope polypeptide, wherein said receptor-binding domain is from a virus selected from the group consisting of HIV, HTLV-1, hepatitis virus, vesicular stomatitis virus, cytomegalovirus, and influenza virus; wherein the insertion point is in a region of the first polypeptide that aligns with amino acids 152 to 181 of SEQ ID NO:2 following a sequence alignment of SEQ ID NO:2 with said polypeptide sequence of a murine or feline leukemia virus envelope polypeptide whose amino acid sequence is at least 70% identical to SEQ ID NO:2; and wherein the chimeric viral envelope polypeptide is capable of binding to the receptor of the second polypeptide sequence.