• Media type: E-Article
  • Title: Charge Cluster-to-Alanine Scanning of UL128 for Fine Tuning of the Endothelial Cell Tropism of Human Cytomegalovirus
  • Contributor: Schuessler, Andrea; Sampaio, Kerstin Laib; Sinzger, Christian
  • Published: American Society for Microbiology, 2008
  • Published in: Journal of Virology, 82 (2008) 22, Seite 11239-11246
  • Language: English
  • DOI: 10.1128/jvi.01069-08
  • ISSN: 0022-538X; 1098-5514
  • Origination:
  • Footnote:
  • Description: ABSTRACT The viral genes UL128, UL130, and UL131A have been identified as major determinants of endothelial cell (EC) tropism of human cytomegalovirus (HCMV), with deletion of either gene causing a null phenotype. We hypothesized that a functional scanning of these genes by minor genetic modifications would allow for the generation of mutants with an intermediate phenotype. By combining charge cluster-to-alanine (CCTA) mutagenesis with markerless mutagenesis of a bacterial artificial chromosome-cloned endotheliotropic HCMV strain, we analyzed UL128 in order to identify functional sites and hence enable targeted modulation of the EC tropism of HCMV. A total of nine mutations in eight charge clusters were tested. Three of the CCTA mutations severely reduced EC tropism, three were irrelevant, two had a weak effect on cell tropism, and one mutation in the most C-terminal cluster caused an intermediate phenotype. All of the highly effective mutations were located in a core region (amino acids 72 to 106) which appears to be particularly crucial for EC tropism. The intermediate effect of mutations in the C-terminal cluster could be modulated by varying the number of amino acids replaced with alanine. This study provides a rational approach for targeted modulation of HCMV cell tropism, which may aid in the development of HCMV strains with a desired degree of attenuation.
  • Access State: Open Access