Differential growth of U and M type infectious haematopoietic necrosis virus in a rainbow trout-derived cell line, RTG-2.
نویسندگان
چکیده
Infectious haematopoietic necrosis virus (IHNV) is one of the most important viral pathogens of salmonids. In rainbow trout, IHNV isolates in the M genogroup are highly pathogenic, while U genogroup isolates are significantly less pathogenic. We show here that, at a multiplicity of infection (MOI) of 1, a representative U type strain yielded 42-fold less infectious virus than an M type strain in the rainbow trout-derived RTG-2 cell line at 24 h post-infection (p.i.). However, at an MOI of 10, there was only fivefold difference in the yield of infectious virus between the U and M strains. Quantification of extracellular viral genomic RNA suggested that the number of virus particles released from cells infected with the U strain at a MOI of 1 was 47-fold lower than from M-infected cells, but U and M virions were equally infectious by particle to infectivity ratios. At an MOI of 1, U strain intracellular viral genome accumulation and transcription were 37- and 12-fold lower, respectively, than those of the M strain at 24 h p.i. Viral nucleocapsid (N) protein accumulation in U strain infections was fivefold lower than in M strain infections. These results suggest that the block in U type strain growth in RTG-2 cells was because of the effects of reduced genome replication and transcription. The reduced growth of the U strain does not seem to be caused by defective genes, because the U and M strains grew equally well in the permissive epithelioma papulosum cyprini cell line at an MOI of 1. This suggests that host-specific factors in RTG-2 cells control the growth of the IHNV U and M strains differently, leading to growth restriction of the U type virus during the RNA synthesis step.
منابع مشابه
Restricted growth of U-type infectious haematopoietic necrosis virus (IHNV) in rainbow trout cells may be linked to casein kinase II activity.
Previously, we demonstrated that a representative M genogroup type strain of infectious haematopoietic necrosis virus (IHNV) from rainbow trout grows well in rainbow trout-derived RTG-2 cells, but a U genogroup type strain from sockeye salmon has restricted growth, associated with reduced genome replication and mRNA transcription. Here, we analysed further the mechanisms for this growth restric...
متن کاملIsolation and Identification of the Infectious Haematopoietic Necrosis Virus (IHNV)-like Agent from Farmed Rainbow Trout (Oncorhynchus mykiss) from Iran
متن کامل
Growth of fish cell lines on microcarriers.
Microcarrier beads were evaluated as substrates for the propagation of five anchorage-dependent fish cell lines. Growth of rainbow trout gonad (RTG-2) and Atlantic salmon cells was limited on microcarriers maintained in suspension. However, stationary microcarriers were suitable substrates for the growth of RTG-2, AS, Chinook salmon embryo (CHSE-214), and fathead minnow cells. Cell yields range...
متن کاملInduction of the Mx protein of rainbow trout Oncorhynchus mykiss in vitro and in vivo with poly I : C dsRNA and infectious hematopoietic necrosis virus
Expression of the Mx protein of rainbow trout was analyzed after induction by poly I:C dsRNA and infectious hematopoietic necrosis virus (IHNV). Poly I:C dsRNA-treated rainbow trout gonad (RTG-2) cells expressed Mx protein that was detectable by immunoblot analysis at 24 h post induction. Increased expression was observed at 48 h and then declined by 72 h post induction. In contrast, IHNV was n...
متن کاملPhylogenetic relationships of Iranian Infectious Pancreatic Necrosis Virus (IPNV) based on deduced amino acid sequences of genome segment A and B cDNA
Infectious Pancreatic Necrosis Virus (IPNV) is the causal agent of a highly contagious disease that affects many species of fish and shellfish. This virus causes economically important diseases of farmed rainbow trout, Oncorhynchus mykiss, in Iran which is often associated with the transmission of pathogens from European resources. In this study, moribund rainbow trout fry were collected during...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Journal of fish diseases
دوره 33 7 شماره
صفحات -
تاریخ انتشار 2010