2 PUTATIVE AFRICAN SWINE FEVER VIRUS HELICASES SIMILAR TO YEAST DEAH PRE-MESSENGER-RNA PROCESSING PROTEINS AND VACCINIA VIRUS ATPASES D11L AND D6R

Two open reading frames (ORFs) of African swine fever virus (ASFV) enc oding putative helicases have been sequenced. The two genes, termed D1 133L and B962L, are located in the central region of the viral genome, but are separated by about 40 kb of DNA. Both genes are expressed lat e during ASFV infection of Vero cells, after replication of viral DNA has begun. Contiguous to D1133L, three other ORFs (D129L, D79L and D33 9L), encoding putative proteins of unknown function, have been sequenc ed. Proteins D1133L and B962L contain the amino acid motifs that chara cterize helicases of superfamily II. D1133L is most similar to a group of putative helicases which includes two proteins of vaccinia virus ( D11L and D6R) involved in transcription of the viral genome, their hom ologues in other poxviruses, the protein encoded by ORF 4 of the yeast plasmids, pGKL2 and pSKL, and the previously identified ASFV protein, Q706L. B962L resembles a group of RNA-helicase-like proteins which in cludes three proteins of Saccharomyces cerevisiae involved in pre-mRNA splicing (PRP2, PRP16 and PRP22), Drosophila melanogaster KURZ and ML E, and vaccinia virus I8R.