COMPARISON OF THE POLYMERASES (L GENES) OF SPRING VIREMIA OF CARP VIRUS AND INFECTIOUS HEMATOPOIETIC NECROSIS VIRUS

We have determined the partial nucleotide sequences of the polymerase genes of the fish rhadboviruses, spring viremia of carp virus (SVCV) a nd infectious hematopoietic necrosis virus (IHNV). At this point we ha ve deduced the amino acid sequences and analysed the first 1 400 amino acids comp prising two thirds of the polymerase genes of SVCV and IHN V. We have compared sequence similarities of SVCV and IHNV polymerases with other rhabdovirus and paramyxovirus polymerases. The SVCV polyme rase showed the closest relationship with the vesicular stomatitis vir us polymerases and also shared significant sequence identity with the polymerase of rabies virus. Other rhabdovirus and paramyxovirus polyme rases showed lower sequences identities with the SVCV polymerase. The IHNV polymerase shared a relatively low amino acid sequence identity w ith the rabies virus polymerase, and similar low identities with other rhabdovirus and paramyxovirus polymerases. Several domains of various lengths were conserved in the virus polymerases included in this stud y. These domains were less conserved in the IHNV polymerase than in th e SVCV polymerase, and some of the domains present in the other polyme rases were not identified in the IHNV. These preliminary results indic ate that SVCV is closely related to mammalian vesiculoviruses and that IHNV may be only distantly related to mammalian lyssa and vesiculotyp e rhabdoviruses.