Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Genomics of West Nile viruses from South Africa

Dissertation (MSc)--University of Pretoria, 2013.

Saved in:
Bibliographic Details
Other Authors: Bastos, Armanda D.S.
Format: Thesis
Language:English
Published: University of Pretoria 2014
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613528258510848
access_status_str Open Access
author2 Bastos, Armanda D.S.
author_browse Bastos, Armanda D.S.
author_facet Bastos, Armanda D.S.
collection Thesis
dc_rights_str_mv © 2013 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Dissertation (MSc)--University of Pretoria, 2013.
format Thesis
id oai:repository.up.ac.za:2263/32944
institution University of Pretoria (South Africa)
language English
last_indexed 2026-06-10T12:37:34.848Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2014
publishDateRange 2014
publishDateSort 2014
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/32944 Genomics of West Nile viruses from South Africa Bastos, Armanda D.S. Abolnik, Celia Kortenhoeven, Cornell West Nile viruses South Africa Genus Flavivirus Infectious WNV clone UCTD Dissertation (MSc)--University of Pretoria, 2013. West Nile Virus (WNV) forms part of the Japanese encephalitis serocomplex in the genus Flavivirus, family Flaviviridae. This enveloped positive single-stranded RNA (+ssRNA ) virus is the etiological agent of West Nile fever, and in more severe cases WNV neuroinvasive disease, in both humans and animals. WNV is distributed worldwide and is phylogenetically classified into five distinct lineages. The WNV genome is ~11 Kb in length and encodes a single open reading frame (ORF) that is post-translationally cleaved into three structural proteins and seven non-structural proteins. In this study, two contemporary and two historic South African WNV strains were genetically characterised as lineage 2 strains based on complete genome sequences. Genetic change as a result of passage number and propagation system was quantified on both the consensus genome- and quasispecies level. A lack of variation was observed amongst the consensus genome sequences of WNV strains subject to changes in propagation system from BHK-21 cell culture to mouse brain and vice versa. In contrast, variation amongst the latter was observed on the quasispecies level. Genome-wide single nucleotide polymorphism (SNP) profiles as well as full-length haplotype sequences reconstructed from ultra deep sequence data indicated that high levels of quasispecies diversity persists, particularly in the capsid gene region, during changes in propagation environment. The changes in frequency of variants were consistent throughout isolates propagated in different systems. The increased variation in the capsid gene region may result from selective pressures brought about by differences in host cell type between propagation systems. This study is the first to demonstrate quasispecies dynamics resulting from changes in propagation system of a lineage 2 WNV based on the reconstruction of full-length haplotype sequences from ultra deep sequence data. The approach demonstrates a cost-effective alternative to the estimation of viral population structure in light of viral evolutionary dynamics, which may in turn be assessed by the single plasmid reverse genetic system designed in this study. Although early attempts at rescuing an infectious WNV clone were unsuccessful, the system shows promise in the application of future studies concerning vaccine and diagnostic development, virulence studies and disease control. gm2013 Zoology and Entomology Unrestricted 2014-01-09T11:12:45Z 2014-01-09T11:12:45Z 2013-09-06 2013-12-12 Dissertation Kortenhoeven, C 2013, 'Genomics of West Nile viruses from South Africa', MSc dissertation, University of Pretoria, Pretoria, viewed yymmdd <http://hdl.handle.net/2263/32944> C13/9/868/gm http://hdl.handle.net/2263/32944 en © 2013 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle West Nile viruses
South Africa
Genus Flavivirus
Infectious WNV clone
UCTD
Genomics of West Nile viruses from South Africa
title Genomics of West Nile viruses from South Africa
title_full Genomics of West Nile viruses from South Africa
title_fullStr Genomics of West Nile viruses from South Africa
title_full_unstemmed Genomics of West Nile viruses from South Africa
title_short Genomics of West Nile viruses from South Africa
title_sort genomics of west nile viruses from south africa
topic West Nile viruses
South Africa
Genus Flavivirus
Infectious WNV clone
UCTD
url http://hdl.handle.net/2263/32944