PhD (Western Ontario)
Research areas: Virology, Molecular Biology, Biochemistry, Genetics, Transcription, Translation, and RNA structure/function
The focus of the research in our laboratory is to understand, at a molecular level, fundamental processes that are utilized by RNA viruses during their infection of host cells. To study these processes we use a messenger- or positive-sensed single-stranded (ss) RNA virus, Tomato bushy stunt virus (TBSV), as our model pathogen. This plant virus is fundamentally similar to many animal-infecting positive-sensed RNA viruses (e.g. Poliovirus, Hepatitis C virus etc.), however TBSV offers several advantages: it has a small and simple genome; studies can be performed in convenient and relatively inexpensive experimental systems; ethical concerns related to the use of animals can be avoided and; the virus is not infectious to humans or other animals.
The 4.8 kb long ssRNA genome of TBSV is directly involved in several key viral processes that are of interest to us. These include: (i) 5′ cap- & poly(A) tail-independent translation of viral proteins; (ii) replication of the viral RNA genome; and (iii) transcription of viral subgenomic (sg) mRNAs. RNA sequences and structures within the ssRNA TBSV genome are involved in each of these processes. Our research aims to: (a) determine the structure-function relationship of important RNA elements within the genome; (b) identify and characterize viral and host proteins that interact with these RNA elements and: (c) determine the molecular mechanisms by which these RNA elements and protein factors mediate the different processes. This research on the fundamental steps in the reproductive cycle of this virus will provide a better understanding of the events leading to the initiation and successful establishment of viral infections in host cells. In turn, this information will be useful for the development of effective anti-viral strategies.
Chkuaseli T, Newburn LR, Bakhshinyan D, White KA. (2015) Protein expression strategies in Tobacco necrosis virus-D. Virology 486:54-62.
Ashton P, Wu B, D'Angelo J, Grigull J, White KA (2015) Biologically-supported structural model for a viral satellite RNA. Nucleic Acids Res. 43:9965-9977.
White KA. (2015) The polymerase slips and PIPO exists. EMBO Rep. 16:885-886.
Gunawardene CD, Jaluba K, White KA. (2015) Conserved motifs in a tombus virus polymerase modulate genome replication, subgenomic transcription, and amplification of defective interfering RNAs. J. Virol. 89:3236-3246.
Newburn LR, White KA. (2014) Cis-acting RNA elements in positive-strand RNA plant virus genomes. Virology 479-480:434-443.
Nicholson BL, White KA. (2014) Functional long-range RNA-RNA interactions in plus-strand RNA viruses. Nature Reviews - Microbiology 12(7):493-504.
Newburn L, Nicholson BL, Yosefi M, and White KA. (2014). Translational Readthrough in Tobacco necrosis virus-D. Virology 450-451:258-265.
Wu B, Grigull J, Ore MO, Morin S, and White KA. (2013) Global Organization of a Plus-strand RNA Virus Genome. PLoS Pathogens 9(5):e1003363.
Nicholson BL, Zaslaver O, Mayberry LK, Browning KS, White KA. (2013) Tombusvirus Y-shaped translational enhancer forms a complex with eIF4F and can be functionally replaced by heterologous translational enhancers. J. Virol. 87:1872-1883.