|Van Etten, James|
Submitted to: Virology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/20/1995
Publication Date: N/A
Citation: Interpretive Summary: Currently, African swine fever virus (ASFV) is the sole member of an unnamed DNA virus family. Chlorella virus (CV) is a large polyhedral DNA containing virus that replicates in a unicellular, eukaryotic green alga. Like ASFV, CV is morphologically similar to iridoviruses and its DNA structure resembles that of poxviruses such as vaccinia virus. Because of these similarities, we hypothesized that ASFV and CV may be related viruses, perhaps sharing a distant common ancestor and that knowledge of CV might provide some insight into complexities of ASFV. To examine this question we identified and analyzed the genes contained within a variable region of the CV DNA molecule and compared them to those present in ASFV. CV genes showed little similarity to those of ASFV. This result indicates that while these two viruses share some structural features, they are different from one another at the genetic level and unlikely to be related.
Technical Abstract: Analysis of 94 kb of DNA, located between map positions 88 and 182 kb in the 330-kb chlorella virus PBCV-1 genome, revealed 195 open reading frames (ORFs) 65 codons or longer. One hundred and five of the 195 ORFs were considered major ORFs. Twenty-six of the 105 major ORFs resembled genes in the databases including three chitinases, a chitosanase, three serine/threonine protein kinases, two additional protein kinases, a tyrosine protein phosphatase, two ankyrins, an ornithine decarboxylase, a copper/ zinc-superoxide dismutase, a proliferating cell nuclear antigen, a DNA polymerase, a fibronectin-binding protein, the yeast Ski2 protein, an adenine DNA methyltransferase and its corresponding DNA site-specific endonuclease, and an amidase. The genes for the 105 major ORFs were evenly distributed along the genome and, except for one noncoding 1788-nucleotide stretch, the genes were close together. Unexpectedly, a 900-bp region in the 1788-bp noncoding sequence resembled a CpG island.