Spacers Increase the Accessibility of Peptide Ligands Linked to the Carboxyl Terminus of Adenovirus Minor Capsid Protein IX
AUTOR(ES)
Vellinga, Jort
FONTE
American Society for Microbiology
RESUMO
The efficiency and specificity of gene transfer with human adenovirus (hAd)-derived gene transfer vectors would be improved if the native viral tropism could be modified. Here, we demonstrate that the minor capsid protein IX (pIX), which is present in 240 copies in the Ad capsid, can be exploited as an anchor for heterologous polypeptides. Protein IX-deleted hAd5 vectors were propagated in hAd5 helper cells expressing pIX variants, with heterologous carboxyl-terminal extensions of up to 113 amino acids in length. The extensions evaluated consist of alpha-helical spacers up to 75 Å in length and to which peptide ligands were fused. The pIX variants were efficiently incorporated into the capsids of Ad particles. On intact particles, the MYC-tagged-pIX molecules were readily accessible to anti-MYC antibodies, as demonstrated by electron microscopic analyses of immunogold-labeled virus particles. The labeling efficiency improved with increasing spacer length, suggesting that the spacers lift and expose the ligand at the capsid surface. Furthermore, we found that the addition of an integrin-binding RGD motif to the pIX markedly stimulated the transduction of coxsackievirus group B and hAd receptor-deficient endothelioma cells, demonstrating the utility of pIX modification in gene transfer. Our data demonstrate that the minor capsid protein IX can be used as an anchor for the addition of polypeptide ligands to Ad particles.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=371045Documentos Relacionados
- Engineering of Adenovirus Vectors Containing Heterologous Peptide Sequences in the C Terminus of Capsid Protein IX
- Protein IX, a minor component of the human adenovirus capsid, is essential for the packaging of full length genomes.
- The Subgenus-Specific C-Terminal Region of Protein IX Is Located on the Surface of the Adenovirus Capsid
- The Coiled-Coil Domain of the Adenovirus Type 5 Protein IX Is Dispensable for Capsid Incorporation and Thermostability
- Screening for receptor ligands using large libraries of peptides linked to the C terminus of the lac repressor.