%0 Journal Article
%T Molecular characterization of the virulent infectious hematopoietic necrosis virus (IHNV) strain 220-90
%A Arun Ammayappan
%A Scott E LaPatra
%A Vikram N Vakharia
%J Virology Journal
%D 2010
%I BioMed Central
%R 10.1186/1743-422x-7-10
%X The complete genomic sequence of IHNV strain 220-90 was determined from the DNA of six overlapping clones obtained by RT-PCR amplification of genomic RNA. The complete genome sequence of 220-90 comprises 11,133 nucleotides (GenBank GQ413939) with the gene order of 3'-N-P-M-G-NV-L-5'. These genes are separated by conserved gene junctions, with di-nucleotide gene spacers. An additional uracil nucleotide was found at the end of the 5'-trailer region, which was not reported before in other IHNV strains. The first 15 of the 16 nucleotides at the 3'- and 5'-termini of the genome are complementary, and the first 4 nucleotides at 3'-ends of the IHNV are identical to other novirhadoviruses. Sequence homology and phylogenetic analysis of the glycoprotein genes show that 220-90 strain is 97% identical to most of the IHNV strains. Comparison of the virulent 220-90 genomic sequences with less virulent WRAC isolate shows more than 300 nucleotides changes in the genome, which doesn't allow one to speculate putative residues involved in the virulence of IHNV.We have molecularly characterized one of the well studied IHNV isolates, 220-90 of genogroup M, which is virulent for rainbow trout, and compared phylogenetic relationship with North American and other strains. Determination of the complete nucleotide sequence is essential for future studies on pathogenesis of IHNV using a reverse genetics approach and developing efficient control strategies.The infectious hematopoietic necrosis virus (IHNV) is probably one of the most important fish viral pathogens causing acute, systemic and often virulent disease predominantly in both wild and cultured salmon and trout [1,2]. The first reported epidemics of IHNV occurred in sockeye salmon (Oncorhynchus nerka) fry at Washington and Oregon fish hatcheries during the 1950s [3-5]. IHNV is native to salmonids of the Pacific Northwest region of North America and its current geographical range extends from Alaska to northern California along the Pa
%U http://www.virologyj.com/content/7/1/10