Research Interests
My current interests center on the evolution of reproductive structures in Conifers from a developmental genetic perspective. Gymnosperms and angiosperms share a common ancestor around 300 MYA and the genetic system for the specification of gymnosperm and angiosperm reproductive organ identity was more than likely derived from a functionally related system in the common ancestor to all seed plants. In angiosperms floral organ identity is primarily determined by interactions of five type II MADS box genes (ABCDE) and clear homologs of the A/E, B and C/D lineages are found in gymnosperms. Particularly interesting in the evolution of seed plant reproductive structures are B-class genes. In both angiosperms and gymnosperms, B-like gene expression is associated with male reproductive structures, the pollen producing organs and male cones respectively. Angiosperm and gymnosperm female reproductive structures, the carpels (but not necessarily ovules) and female cones, respectively, exhibit a lack of B-like gene expression. One theory that remains untested is that a related gene lineage, known as Bsister genes, is required for female reproductive identity in angiosperms and gymnosperms. However, based on current data, it is difficult to make generalizations about the evolutionary and developmental roles of B-like genes in seed plants. By studying the evolutionary history of B-like genes and Bsister genes in diverse gymnosperms, we will elucidate the evolutionary relationships of the putative reproductive identity genes in extant seed plants. This research will establish a broader comparative framework that will advance the study of the evolution and development of flower and cone reproductive structures and enable us to address questions of homology and the evolution of diverse reproductive structures in extant gymnosperms. Ultimately, the goal is to clarify the question of the origin of angiosperms by characterizing how the reproductive features of a flower (for example a water lily) are related to those of a gymnosperm (for example a pine cone).
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