Elizabeth S. Dennis
University of Technology Sydney
|
Primary Section: 62, Plant, Soil, and Microbial Sciences Secondary Section: 25, Plant Biology Membership Type:
International Member
(elected 2021)
|
Biosketch
Liz Dennis has researched the molecular basis of plant processes over many years. She analysed how plants respond to low oxygen conditions and the role of the ALCOHOL DEHYDROGENASE gene in the anaerobic response. Later work included the isolation of the FLC gene that encodes a repressor of flowering that is epigenetically down regulated by vernalization. Studies on the FLC gene provided an understanding of the mechanism of vernalization, important in the induction of flowering in spring.
Liz was born in Sydney, Australia and attended Sydney University for her B.Sc. and PhD degrees. She did Post-Doctoral work with Julius Marmur at Albert Einstein College of Medicine, a time at the University of Papua New Guinea and joined CSIRO Plant Industry in Canberra, Australia. She was appointed to UTS as a Distinguished Professor in 2010. She spent a sabbatical year at Stanford University with Paul Berg on a Fulbright Fellowship. She is a fellow of the Australian Academy of Science and of the Australian Academy of Technological Sciences and Engineering. She was awarded the inaugural Prime Minister’s prize for Science (in 2000) which she shared with Jim Peacock.
Research Interests
Dennis’s current research focuses on hybrid vigour where the yield of progeny of a cross is higher than that of either parent. The hybrid advantage functions only in the F1, fresh hybrid seed must be purchased each planting. Her laboratory has selected, in Arabidopsis and in the crop plants rice and lentil, Hybrid Mimics, pure breeding lines that maintain the hybrid advantage, avoiding the necessity of producing new F1 hybrids each generation. Hybrid Mimics may produce higher yielding crops without the need to purchase hybrid seed each planting.
Hybrids and Hybrid Mimics achieve their increased yield through similar changes in gene expression and Hybrid Mimics have proved a powerful tool for identifying genes and metabolic pathways critical for the generation of the vigour phenotype including the auxin and salicylic acid hormone pathways which control the growth of plants. Hybrids and Mimics both germinate and establish photosynthesis earlier than parents. This early advantage leads to earlier emergence of leaves and the development of a larger leaf area at any time.
Dennis and her colleagues described a novel epigenetic process, Trans Chromosomal Methylation in hybrids where the methylation pattern of one allele is acquired by the alternative allele in the F1.
