The hypervariable domain of the murine leukemia virus surface protein tolerates large insertions and deletions, enabling development of a retroviral particle display system

摘要: The surface proteins (SU) of murine type-C retroviruses have a central hypervariable domain devoid cysteine and rich in proline. This 41-amino-acid region Friend ecotropic leukemia virus SU was shown to be highly tolerant insertions deletions. Viruses which either the N-terminal 30 amino acids or C-terminal 22 this were replaced by 7-amino-acid sequence ASAVAGA fully infectious. Insertions at N terminus, center, C terminus had little effect on envelope protein (Env) function, while insertion position 10 following partially destabilized association between transmembrane subunits Env. Large, complex domains (either 252-amino-acid single-chain antibody binding [scFv] 96-amino-acid V1/V2 HIV-1 containing eight N-linked glycosylation sites two disulfides) did not interfere with Env function when inserted center portions domain. scFv into mediate antigen viral particles, demonstrating that it folded active conformation displayed virion. Both positive negative enrichment virions expressing achieved using monoclonal specific for conformational epitope presented sequence. These results indicated does contain any structure is essential demonstrated can used extend particle display methodologies require expression eukaryotic cells proper folding.