Submitted to: International Conference on Poxviruses and Iridoviruses Proceedings
Publication Type: Proceedings
Publication Acceptance Date: September 4, 2004
Publication Date: September 4, 2004
Citation: Neilan, J.G., Kutish, G.F., Lu, Z., Burrage, T.G., Zsak, L., Rock, D.L. 2004. The african swine fever virus multi gene family 360 member, 3hl, forms homodimers [abstract]. International Conference on Poxviruses and Iridoviruses Proceedings. p. 160.
Previously we have shown that ASFV multigene family 360 (MGF360) genes play critical roles in: ASFV infection of swine macrophage cell cultures, the primary target cell types for ASFV; swine virulence and viral pathogenesis in soft ticks(Ornithodorus porcinus porcinus).The ASFV PR4 isolate contains seventeen MGF360 genes, ranging in size from 237 to 387 amino acid residues, which are located in the left and right variable regions of the PR4 genome. Database searches have failed to identify homologs of these genes. PR4 recombinant viruses in which blocks containing deletions of multiple MGF360 genes in the left variable region of the genome were constructed. Analysis of these recombinant viruses indicate that the most severely growth restricted recombinant viruses are associated with larger deletions suggesting these genes may function either co-operatively, as oligomers or they may perform complementing function. Three contiguous MGF360 genes (3HL, 3IL and 3LL) had the most significant affect on ASFV replication in both swine macrophage and in ticks, with 3HL having the most profound affect. To further characterize 3HL, a recombinant PR4 virus containing 3HL tagged with a HA epitope, was constructed. Western blot analysis show 3HL to be expressed early in the infection cycle. Yeast two hybrid analysis was used to identify proteins which interact with 3HL. A cDNA library of 2x106 independent clones was constructed in the Gal-4 activation domain vector, pGBKT7-Rec AD, using mRNA isolated from ASFV infected swine macrophages at various times post infection. The library was screened with 3HL cloned in frame in the Gal4 DNA binding domain vector, pGADT7. Two interactors were obtained and identified as 3HL by sequence analysis suggesting 3HL may function as a homodimer.