Project description:Zika virus (ZIKV) infection causes microcephaly and has been linked to other brain abnormalities. How ZIKV impairs brain development and function remains elusive. Here we systematically profiled transcriptomes of human neural progenitor cells (hNPCs) and astrocytes exposed to Asian ZIKVC, African ZIKVM, and Dengue virus (DENV). DENV causes distinct gene expression changes; and ZIKV has a broader impact on the expression of gene involved in DNA replication and repair. While overall expression profiles are similar, ZIKVC, but not ZIKVM, induces upregulation of viral response genes. Upon ZIKV infection, astrocytes exhibit more prominent transcriptome changes than hNPCs, particularly enriching genes related to inflammatory response and cytokine production pathways. Our analyses reveal cell-type- and strain-specific molecular signatures associated with ZIKV infection, and identify astrocytes as a major direct target of ZIKV. Further investigation of ZIKV-host interactions based our transcriptomic datasets may help to illuminate neural virulence determinants of ZIKV in patients. Gene Expression Analyses of the cells infected with different flaviviruses
Project description:Brain abnormalities and congenital malformations have been linked to the circulating strain of Zika virus (ZIKV) in Brazil since 2016 during the microcephaly outbreak; however, the molecular mechanisms behind several of these alterations and differential viral molecular targets have not been fully elucidated. Here we explore the proteomic alterations induced by ZIKV by comparing the Brazilian (Br ZIKV) and the African (MR766) viral strains, in addition to comparing them to the molecular responses to the Dengue virus (DENV). Neural stem cells (NSCs) derived from induced pluripotent stem (iPSCs) were cultured both as monolayers and in suspension (resulting in neurospheres), which were then infected with ZIKV (Br ZIKV or ZIKV MR766) or DENV to assess alterations within neural cells. Large-scale proteomic analyses allowed the comparison not only between viral strains but also regarding the two- and three-dimensional cellular models of neural cells derived from iPSCs, and the effects on their interaction. Altered pathways and biological processes were observed, related to cell death, cell cycle dysregulation, and neurogenesis. These results reinforce already published data and provide further information regarding the biological alterations induced by ZIKV and DENV.
Project description:Zika virus (ZIKV) infection causes microcephaly and has been linked to other brain abnormalities. How ZIKV impairs brain development and function remains elusive. Here we systematically profiled transcriptomes of human neural progenitor cells (hNPCs) exposed to Asian ZIKVC, African ZIKVM, and Dengue virus (DENV). DENV causes distinct gene expression changes; and ZIKV has a broader impact on the expression of gene involved in DNA replication and repair. While overall expression profiles are similar, ZIKVC, but not ZIKVM, induces upregulation of viral response genes. Our analyses reveal virus- and strain-specific molecular signatures associated with ZIKV infection. Further investigation of ZIKV-host interactions based our transcriptomic datasets may help to illuminate neural virulence determinants of ZIKV in patients.
Project description:Zika virus (ZIKV) is a mosquito-transmitted positive-sense RNA virus in the family Flaviviridae. ZIKV infections are associated with neurodevelopmental deficiencies termed Congenital Zika Syndrome. ZIKV strains are grouped into three phylogenetic lineages: East African, West African, and Asian, which contains the American lineage. RNA virus genomes exist as genetically-related sequences. The heterogeneity of these viral populations is implicated in viral fitness, and genome diversity is correlated to virulence. This study examines genetic diversity of representative ZIKV strains from all lineages utilizing next generation sequencing (NGS). Inter-lineage diversity results indicate that ZIKV lineages differ broadly from each other; however, intra-lineage comparisons of American ZIKV strains isolated from human serum or placenta show differences in diversity when compared to ZIKVs from Asia and West Africa. This study describes the first comprehensive NGS analysis of all ZIKV lineages and posits that sub-consensus-level diversity may provide a framework for understanding ZIKV fitness during infection.
Project description:Brain abnormalities and congenital malformations have been linked to the circulating strain of Zika virus (ZIKV) in Brazil since 2016 during the microcephaly outbreak; however, the molecular mechanisms behind several of these alterations and differential viral molecular targets have not been fully elucidated. Here we explore the proteomic alterations induced by ZIKV by comparing the Brazilian (Br ZIKV) and the African (MR766) viral strains, in addition to comparing them to the molecular responses to the Dengue virus (DENV). Neural stem cells (NSCs) derived from induced pluripotent stem (iPSCs) were cultured both as monolayers and in suspension (resulting in neurospheres), which were then infected with ZIKV (Br ZIKV or ZIKV MR766) or DENV to assess alterations within neural cells. Large-scale proteomic analyses allowed the comparison not only between viral strains but also regarding the two- and three-dimensional cellular models of neural cells derived from iPSCs, and the effects on their interaction. Altered pathways and biological processes were observed, related to cell death, cell cycle dysregulation, and neurogenesis. These results reinforce already published data and provide further information regarding the biological alterations induced by ZIKV and DENV.
Project description:ZIKV strains belong to three phylogenetic lineages: East African, West African, and Asian/American. RNA virus genomes exist as populations of genetically-related sequences whose heterogeneity may impact viral fitness, evolution, and virulence. The genetic diversity of representative ZIKVs (N=7) from each lineage was examined using next generation sequencing (NGS) paired with downstream Shannon entropy calculation and single nucleotide variant (SNV) analysis. This comprehensive analysis of ZIKV genetic diversity provides insight into the genetic diversity of ZKIV and repository of SNV positions across lineages.
Project description:Ribosome profiling (Ribo-Seq) (maps positions of translating ribosomes on the transcriptome) and RNA-Seq (quantifies the transcriptome) analysis of African green monkey (Vero E6) cells and Aedes albopictus (C6/36) cells infected with Zika Virus (ZIKV) strain PE243. Cells were harvested at 24 h post infection (p.i.) and Ribo-Seq and RNA-Seq libraries were prepared and deep sequenced.
Project description:Zika virus (ZIKV), a pathogen of global health concern, is transmitted to humans by Aedes mosquitoes. However, the molecular interactions between the vector and the virus remain largely unexplored. We demonstrated that ZIKV and dengue virus (DENV) have similar tropism and infection kinetics in two mosquito strains with different degrees of susceptibility to infection. Comparison of Aedes aegypti’s molecular responses to ZIKV and DENV infection indicated that around 40% of the mosquito’s infection-responsive transcriptome is virus-specific. Regulated genes also included key factors of the mosquito’s anti-viral immunity, pointing to the possible involvement of the Toll innate immune pathway. Comparison of ZIKV and DENV infection-responsive transcriptome data to those for yellow fever virus and West Nile virus identified 26 genes likely to play key roles in virus infection of Aedes mosquitoes. Through reverse genetic analyses, we showed that the Toll and the Jak/Stat innate immune pathways mediate increased resistance to ZIKV infection, and the virus use vATPase and inosine-5’-monophosphate dehydrogenase as mosquito’s host factors.