Jean Finnegan

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Elizabeth Jean Finnegan FAA is an Australian botanist who researches plant flowering processes and epigenetic regulation in plants. [1] [2] [3] She currently works at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) as a senior scientist, leading research on the "Control of Floral Initiation", part of the CSIRO Agriculture Flagship (formerly known as CSIRO Plant Industry). [4]

Contents

Education

Finnegan received her Bachelor of Science (honours) from the University of Adelaide, and her PhD from the University of Adelaide in 1979. Her thesis was Transcriptional studies of bacteriophage 186. [5]

Recognition

Finnegan was elected a Fellow of the Australian Academy of Science in May 2014 on the basis of her world leading research on plant gene expression. [6] Her contribution to plant science includes her early work, cloning the first plant (METI), and her work demonstrating that DNA methylation (a biochemical process that modifies the plant's DNA) is essential for normal plant development [7] and by reducing levels of methylation changes the plant's size and shape, flowering time, structure of the flowers and number of seeds. [8]

In 2012, Finnegan was awarded the Julian Wells Medal for contributions to research on the organisation and expression of the genome. [9]

Finnegan is on the editorial board for BMC Plant Biology. [10]

Research

Finnegan's research focuses on epigenetic mechanisms of flowering processes in plants, specifically, the role of DNA methylation in normal plant development. DNA methylation is a biochemical process that modifies DNA, with Finnegan's work some of the first to show this in plants. She generated plants with reduced levels of DNA methylation using an antisense against METI, and determined the molecular basis for the abnormal phenotypes displayed by plants with reduced levels of methylation. [11] She continues to be a leader in her field through her research on flowering processes and the role of DNA methylation and epigenetics helping to understand the mechanisms contributing to the down-regulation of flowering locus C (FLC) in vernalized plants. [12] [13] The focus of her current research is investigating the role of DNA methylation in regulating traits of agronomic importance in wheat.

Related Research Articles

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<span class="mw-page-title-main">Vernalization</span> Induction of a plants flowering process

Vernalization is the induction of a plant's flowering process by exposure to the prolonged cold of winter, or by an artificial equivalent. After vernalization, plants have acquired the ability to flower, but they may require additional seasonal cues or weeks of growth before they will actually do so. The term is sometimes used to refer to the need of herbal (non-woody) plants for a period of cold dormancy in order to produce new shoots and leaves, but this usage is discouraged.

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<span class="mw-page-title-main">Repressor</span> Sort of RNA-binding protein in molecular genetics

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<span class="mw-page-title-main">RNA-directed DNA methylation</span> RNA-based gene silencing process

RNA-directed DNA methylation (RdDM) is a biological process in which non-coding RNA molecules direct the addition of DNA methylation to specific DNA sequences. The RdDM pathway is unique to plants, although other mechanisms of RNA-directed chromatin modification have also been described in fungi and animals. To date, the RdDM pathway is best characterized within angiosperms, and particularly within the model plant Arabidopsis thaliana. However, conserved RdDM pathway components and associated small RNAs (sRNAs) have also been found in other groups of plants, such as gymnosperms and ferns. The RdDM pathway closely resembles other sRNA pathways, particularly the highly conserved RNAi pathway found in fungi, plants, and animals. Both the RdDM and RNAi pathways produce sRNAs and involve conserved Argonaute, Dicer and RNA-dependent RNA polymerase proteins.

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References

  1. "Dr Jean Finnegan: understanding flowering". CSIRO. 14 October 2013. Archived from the original on 15 December 2014. Retrieved 11 November 2015.
  2. Finnegan, E. J.; Genger, R. K.; Peacock, W. J.; Dennis, E. S. (1998). "DNA Methylation in Plants". Annual Review of Plant Physiology and Plant Molecular Biology. 49: 223–247. doi:10.1146/annurev.arplant.49.1.223. PMID   15012234.
  3. Finnegan, E J; Peacock, W J; Dennis, E S (2000). "DNA methylation, a key regulator of plant development and other processes". Current Opinion in Genetics & Development. 10 (2): 217–223. doi:10.1016/S0959-437X(00)00061-7. PMID   10753779.
  4. "Dr Jean Finnegan: Understanding flowering | CSIRO". Archived from the original on 15 December 2014. Retrieved 11 November 2015.
  5. Finnegan, Elizabeth Jean (1979). Transcriptional studies of bacteriophage 186 (Thesis). Adelaide. hdl:2440/20053.
  6. "Dr Elizabeth Jean Finnegan". Australian Academy of Science. 2014. Archived from the original on 21 December 2016. Retrieved 8 December 2016.
  7. Finnegan, E J; Peacock, W J; Dennis, E S (1996). "Reduced DNA methylation in Arabidopsis thaliana results in abnormal plant development". PNAS. 93 (16): 8449–8454. Bibcode:1996PNAS...93.8449F. doi: 10.1073/pnas.93.16.8449 . PMC   38691 . PMID   8710891.
  8. Finnegan, E J; Peacock, W J; Dennis, E S (1996). "Reduced DNA methylation in Arabidopsis thaliana results in abnormal plant development". PNAS. 93 (16): 8449–8454. Bibcode:1996PNAS...93.8449F. doi: 10.1073/pnas.93.16.8449 . PMC   38691 . PMID   8710891.
  9. "Julian Wells Medal". Victoria, Australia: Lorne Genome Conference. Archived from the original on 25 September 2015. Retrieved 11 November 2015.
  10. "BMC Plant Biology Editorial Board". Archived from the original on 24 November 2011.
  11. "Reduced DNA methylation in Arabidopsis thaliana results in abnormal plant development". October 2014.{{cite journal}}: Cite journal requires |journal= (help)
  12. Finnegan, E J; Dennis, E S (2007). "Vernalization-Induced Trimethylation of Histone H3 Lysine 27 at FLC Is Not Maintained in Mitotically Quiescent Cells". Current Biology. 17 (22): 1978–1983. doi: 10.1016/j.cub.2007.10.026 . PMID   17980595. S2CID   18167488.
  13. Jean Finnegan, E.; Kovac, Kathryn A.; Jaligot, Estelle; Sheldon, Candice C.; James Peacock, W.; Dennis, Elizabeth S. (2005). "The downregulation of FLOWERING LOCUS C (FLC) expression in plants with low levels of DNA methylation and by vernalization occurs by distinct mechanisms". The Plant Journal. 44 (3): 420–432. doi:10.1111/j.1365-313X.2005.02541.x. PMID   16236152.