Skip to main content
U.S. flag

An official website of the United States government

Transcriptome analysis of rainbow trout infected with high and low virulence strains of Infectious hematopoietic necrosis virus

January 15, 2012

There are three main genetic lineages or genogroups of Infectious hematopoietic necrosis virus (IHNV) in N. America. Strains representing the M genogroup are more virulent in rainbow trout relative to the U genogroup. In this study, we used microarray analysis to evaluate potential mechanisms responsible for host-specific virulence in rainbow trout that were given intraperitoneal injections of buffer or a representative M or U type virus strain. Reverse transcriptase quantitative PCR (RT-qPCR) was used to assess viral load and gene expression of select immune genes. Viral load was significantly higher in trout infected with the M virus starting at 24 h post-infection (p.i.) and continuing until 72 h p.i. Microarray analysis of the 48 h time point revealed 153 up-regulated and 248 down-regulated features in response to M virus infection but only 62 up-regulated and 49 down-regulated features following U virus infection. Translation and transcription features were among the most frequent down-regulated features in response to M virus infection and may be associated with the host cell shutoff phenomenon. A greater host cell shutoff response by the M virus may facilitate subversion of the host cell transcriptional machinery and enhance viral replication, suggesting the M virus may be better optimized to manipulate the rainbow trout transcriptional and translational machinery. Anti-viral associated features were the most commonly up-regulated features. A common set of features were up-regulated in both the M and U infection groups, but were induced to a higher magnitude in the M infection group. Gene expression of the anti-viral genes Mx-1 and Vig-1 was correlated but not entirely dependent on viral load in the anterior kidney. Slower replication of the U virus may allow the host more time to induce protective anti-viral immune mechanisms.

Citation Information

Publication Year 2010
Title Transcriptome analysis of rainbow trout infected with high and low virulence strains of Infectious hematopoietic necrosis virus
DOI 10.1016/j.fsi.2010.09.007
Authors Maureen K. Purcell, Inderjit Singh Marjara, William Batts, Gael Kurath, John D. Hansen
Publication Type Article
Publication Subtype Journal Article
Series Title Fish and Shellfish Immunology
Series Number
Index ID 70003672
Record Source USGS Publications Warehouse
USGS Organization Western Fisheries Research Center