Advanced search options

Advanced Search Options 🞨

Browse by author name (“Author name starts with…”).

Find ETDs with:

in
/  
in
/  
in
/  
in

Written in Published in Earliest date Latest date

Sorted by

Results per page:

You searched for subject:(BBTV DNA S4). One record found.

Search Limiters

Last 2 Years | English Only

No search limiters apply to these results.

▼ Search Limiters


Queensland University of Technology

1. Tsao, Theresa Tsun-Hui. Towards the development of transgenic banana bunchy top virus (BBTV)-resistant banana plants : interference with replication.

Degree: 2008, Queensland University of Technology

Banana bunchy top virus (BBTV) causes one of the most devastating diseases of banana. Transgenic virus resistance is now considered one of the most promising strategies to control BBTV. Pathogen-derived resistance (PDR) strategies have been applied successfully to generate plants that are resistant to numerous different viruses, primarily against those viruses with RNA genomes. BBTV is a circular, single-stranded (css) DNA virus of the family Nanoviridae, which is closely related to the family Geminiviridae. Although there are some successful examples of PDR against geminiviruses, PDR against the nanoviruses has not been reported. Therefore, the aim of this thesis was to investigate the potential of BBTV genes to interfere with virus replication when used as transgenes for engineering banana plants resistance to BBTV. The replication initiation protein (Rep) of nanoviruses is the only viral protein essential for viral replication and represents an ideal target for PDR. Therefore, this thesis focused on the effect of wild-type or mutated Rep genes from BBTV satellite DNAs or the BBTV integral genome on the replication of BBTV in banana embryogenic cell suspensions. A new Rep-encoding satellite DNA, designated BBTV DNA-S4, was isolated from a Vietnamese BBTV isolate and characterised. When the effect of DNA-S4 on the replication of BBTV was examined, it was found that DNA-S4 enhanced the replication of BBTV. When the replicative capabilities of DNA-S4 and the previously characterised Rep-encoding BBTV satellite, DNA-S1, were compared, it was found that the amount of DNA-S4 accumulated to higher levels than DNA-S1. The interaction between BBTV and DNA-S1 was also examined. It was found that over-expression of the Rep encoded by DNA-S1 using ubi1 maize polyubiquitin promoter enhanced replication of BBTV. However, when the Rep-encoded by DNA-S1 was expressed by the native S1 promoter (in plasmid pBT1.1-S1), it suppressed the replication of BBTV. Based on this result, the use of DNA-S1 as a possible transgene to generate PDR against BBTV was investigated. The roles of the Rep-encoding and U5 genes of BBTV DNA-R, and the effects of over-expression of these two genes on BBTV replication were also investigated. Three mutants of BBTV DNA-R were constructed; plasmid pUbi-RepOnly-nos contained the ubi1 promoter driving Rep expression from DNA-R, plasmid pUbi-IntOnly-nos contained the ubi1 promoter driving expression of the DNA-R internal gene product (U5), while plasmid pUbi-R.ORF-nos contained the ubi1 promoter driving the expression of both Rep and the internal U5 gene product. The replication of BBTV was found to be significantly suppressed by pUbi-RepOnly-nos, weakly suppressed by pUbi-IntOnly-nos, but strongly enhanced by pUbi-R.ORF-nos. The effect of mutations in three conserved residues within the BBTV Rep on BBTV replication was also assessed. These mutations were all made in the regions in the ATPase motifs and resulted in changes from hydrophilic to hydrophobic residues (i.e. K187→M, D224→I and N268→L). None of…

Subjects/Keywords: banana bunchy top virus; nanoviruses; replication initiation protein (Rep); pathogen-derived resistance; BBTV DNA-R; BBTV DNA-S1; BBTV DNA-S3; BBTV DNA-S4; satellite DNA; ATPase; post-transcriptional gene silencing; RNA silencing suppressor

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Tsao, T. T. (2008). Towards the development of transgenic banana bunchy top virus (BBTV)-resistant banana plants : interference with replication. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/17031/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Tsao, Theresa Tsun-Hui. “Towards the development of transgenic banana bunchy top virus (BBTV)-resistant banana plants : interference with replication.” 2008. Thesis, Queensland University of Technology. Accessed March 01, 2021. https://eprints.qut.edu.au/17031/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Tsao, Theresa Tsun-Hui. “Towards the development of transgenic banana bunchy top virus (BBTV)-resistant banana plants : interference with replication.” 2008. Web. 01 Mar 2021.

Vancouver:

Tsao TT. Towards the development of transgenic banana bunchy top virus (BBTV)-resistant banana plants : interference with replication. [Internet] [Thesis]. Queensland University of Technology; 2008. [cited 2021 Mar 01]. Available from: https://eprints.qut.edu.au/17031/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tsao TT. Towards the development of transgenic banana bunchy top virus (BBTV)-resistant banana plants : interference with replication. [Thesis]. Queensland University of Technology; 2008. Available from: https://eprints.qut.edu.au/17031/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.