title: Medaka haploid embryonic stem cells are susceptible to Singapore grouper iridovirus as well as to other viruses of aquaculture fish species.
abstract: Viral infection is a challenge in high-density aquaculture, as it leads to various diseases and causes massive or even complete loss. The identification and disruption of host factors that viruses utilize for infection offer a novel approach to generate viral-resistant seed stocks for cost-efficient and sustainable aquaculture. Genetic screening in haploid cell cultures represents an ideal tool for host factor identification. We have recently generated haploid embryonic stem (ES) cells in the laboratory fish medaka. Here, we report that HX1, one of the three established medaka haploid ES cell lines, was susceptible to the viruses tested and is thus suitable for genetic screening to identify host factors. HX1 cells displayed a cytopathic effect and massive death upon inoculation with three highly infectious and notifiable fish viruses, namely Singapore grouper iridovirus (SGIV), spring viremia of carp virus (SVCV) and red-spotted grouper nervous necrosis virus (RGNNV). Reverse transcription-PCR and Western blot analyses revealed the expression of virus genes. SGIV infection in HX1 cells elicited a host immune response and apoptosis. Viral replication kinetics were determined from a virus growth curve, and electron microscopy revealed propagation, assembly and release of infectious SGIV particles in HX1 cells. Our results demonstrate that medaka haploid ES cells are susceptible to SGIV, as well as to SVCV and RGNNV, offering a unique opportunity for the identification of host factors by genetic screening.
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore.
authors.forename: Yongming
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: Key Laboratory of Marine Bio-resources Sustainable Utilization, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, PR China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Huang
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Marine Bio-resources Sustainable Utilization, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, PR China.
authors.forename: Youhua
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Key Laboratory of Marine Bio-resources Sustainable Utilization, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, PR China.
authors.forename: Qiwei
authors.initials: Q
authors.lastname: Qin
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore.
authors.forename: Yunhan
authors.initials: Y
authors.lastname: Hong
mesh_terms: D000818:Animals; D017209:Apoptosis; D017756:Aquaculture; D002478:Cells, Cultured; D003588:Cytopathogenic Effect, Viral; D004266:DNA Virus Infections / Q000662:veterinary* / Q000821:virology; D053595:Embryonic Stem Cells / Q000648:ultrastructure / Q000821:virology*; D005393:Fish Diseases / Q000821:virology*; D015967:Gene Expression Regulation, Viral / Q000502:physiology; D006238:Haploidy; D054884:Host-Pathogen Interactions / Q000276:immunology / Q000502:physiology; D017994:Iridovirus / Q000145:classification* / Q000502:physiology* / Q000648:ultrastructure; D008854:Microscopy, Electron; D009990:Oryzias / Q000196:embryology / Q000502:physiology* / Q000821:virology; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism; D059467:Transcriptome; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D012367:RNA, Viral; D014764:Viral Proteins