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I received my doctorate in plant cellular and molecular biology through the Department of Molecular, Cellular, and Developmental Biology at the University of Michigan, Ann Arbor. My dissertation research included the molecular biology, evolution, and biotechnological application of terpenoid scent compound production in Clarkia and Oenothera species in the laboratory of Dr. Eran Pichersky. This turned out to be the first molecular study to characterize a gene involved in floral scent production. More importantly, it triggered my interest in flower development, which is now directed toward the understanding of the flower development of tree species. A number of projects in our lab focus on how MADS-box developmental genes control the formation of flowers in tree species. However, more recently we have characterized a number of MADS-box transcription factors that appear to be involved in the formation of vascular tissues and may be directing events responsible for Whole Plant Formation.
Aspen Tree Vegetative Development
The vascular system of a tree forms an intricately networked system of diverse cell types extending from leaf ends to root tips and virtually every other tissue within the plant. Perhaps the best-known commodity derived from a tree's vascular system is WOOD, a valuable, renewable resource for lumber, paper and energy production. While tree improvement has been the focus of much research, there is not much information available about the genes that control the differentiation and development of the woody vascular tissues that are derived from the meristematic cells of the vascular cambium. Moreover, deforestation resulting from fires and the expansion of cities continues while the demand for wood products is increasing. To sustain the growing need for wood products, alternate strategies focusing on an understanding of the mechanisms of wood differentiation and development are urgently needed to help open the door to improving wood production and wood quality.
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MADS-box genes are homeotic transcription factors that regulate the development of plant tissues as diverse as flowers to root nodules in a wide variety of species including trees. In recent years, an array of MADS-box genes has also been implicated in the regulation of vegetative development. This potentially makes such genes very useful tools for understanding the developmental mechanisms of whole plant growth, but little is known about their function in vascular tissues.
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PTM5 RNA in situ hybridization and
tissue print analysis
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We have obtained data demonstrating the specific expression of MADS-box genes in developing woody tissues of Populus tremuloides (trembling aspen trees). We have characterized one of these MADS-box genes in detail, PTM5, that was demonstrated to have cambium-specific expression. And, we have shown that PTM5 is a novel gene that is likely to be important in controlling the development of primary vascular tissues and spring wood formation responsible for whole tree growth.
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The primary objective of this current work is to define the molecular mechanisms of MADS-box genes, such as PTM5, in the vascular development and wood formation in aspen trees. P. tremuloides is the most wide-spread tree species in North America, and its use as a model system for the study of vascular development is very well warranted.
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Example of an aspen macroarray
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Thus the main aims of this project are to (1) Understand the functional role of PTM5-related MADS-box genes in wood formation using aspen transgenics.
(2) Assess the effects of MADS-box gene manipulation on global gene expression using aspen macro- and mircoarrays. (3) Delineate the temporal, spatial and protein-protein interaction relationships between PTM5-related MADS-box genes during wood formation. (4) Determine the functional regions of the PTM5 promoter that regulate cambial specific expression and seasonal activity. This multidimensional approach to the study of MADS-box gene function in tree vascular development has significant relevance to long-term advances in U.S. Forestry.
Relevant Publications:
Cseke L.J and Podila G.K. (2004) MADS-box Genes in Dioecious Aspen II: A review
of MADS-box genes from trees and their potential in forest biotechnology.
Physiology and Molecular Biology of Plants (In Press).
Cseke L.J, Zheng J, Podila G.K. (2003) Characterization of PTM5 in Aspen: a
MADS-box Gene Expressed During Woody Vascular Development. GENE 318:55-67.
Full Text
Cseke L.J, Sen B, Taylor L, Ravinder N, Karnosky D.F, Podila G.K. (2003)
MADS-box Genes from Dioecious Aspen I: Characterization of PTM1/2 MADS-box
Genes
Homologous to AP1/SQUA. Physiology and Molecular Biology of Plants
9(2):187-196.
Relevant Links:
The University of Alabama in Huntsville
Michigan Technological University,
The University of Arizona,
The University of Michigan
Societies and Colleagues:
American Society of Plant Biologists,
Dr. Gopi K. Podila,
Dr. Chung-Jui Tsai,
Dr. David Karnosky
Molecular Tools
Handbook of Molecular and Cellular Methods in Biology and Medicine,
National Center for Biotechnology Information,
MultAlin Interface,
BoxShade Server,
MADS-box Gene List,
ExPASy Proteomics tools
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