SEQUENCES OF THE N-GENE AND M-GENE OF THE SIGMA-VIRUS OF DROSOPHILA AND EVOLUTIONARY COMPARISON

The genome of the sigma rhabdovirus of Drosophila melanogaster consist s of six genes in the order 3' N-2-3-4-G-L 5'. The nucleotide sequence s of the N and of the fourth genes were determined from cDNA clones. E ach gene contained a single long open reading frame encoding polypepti des with predicted MW of 50 and 25 kDa, respectively. Evidence that th ese genes encode the nucleocapsid N and the matrix M proteins were obt ained using antibodies raised against recombinant proteins derived fro m the cloned genes and expressed in Escherichia coli. The M and N pred icted amino acid sequences were compared with those of other rhabdovir uses. The M protein of sigma virus shared a similar domain arrangement to the other M proteins, but it showed very little sequence conservat ion. The N protein of sigma virus showed no significant homology with its counterpart in SYNV or IHNV and VSHV; it did, however, show sequen ce homology with the N of four vesiculoviruses and two lyssaviruses. T he extent of amino acid identity suggests that sigma virus occupies an intermediate evolutionary position between these two genera. Some con served motifs in the M and N proteins were deduced from the comparison s. (C) 1994 Academic Press, Inc.