Robert Dale ReedAssistant Professor, Ecology & Evolutionary Biology |
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Research Interests |
Evolution and development; butterfly wing patterns. | |
| URL | Lab Page | |
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Academic Distinctions | John Adams Comstock Award - Lepidopterists' Society | |
| Appointments | Hargitt Research Fellow in Cell Biology - Duke University | |
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Research Abstract |
Developmental genetics of Heliconius wing patterns Neotropical Heliconius butterflies are famous for their wing pattern polymorphism and mimicry. There is an active community of researchers working on many aspects of Heliconius biology, including population dynamics, behavior, phylogeny, genetics, and development. The experimental accessibility of this genus at many levels provides an exciting opportunity to produce a highly integrated portrait of the interplay between speciation and morphological evolution. Heliconius is rapidly maturing as a key model system for evolutionary studies, and genomic resources such as linkage maps, BAC libraries, and EST libraries are in various stages of development. I am working closely with the McMillan Lab at North Carolina State University to positionally clone adaptive color pattern genes from the species H. erato. This work is being done in the context of a larger international collaboration to identify color pattern genes across multilple species of Heliconius. We are also sequencing ESTs and developing a large-scale microarray in order to characterize gene expression associated with the development and polymorphism of H. erato wing patterns. Developmental variation in populations A growing body of data shows that development can be robust to variation in parameters such as the timing or level of gene expression. This leads to the prediction that natural populations should be able to host developmental variation that has few obvious phenotypic effects. Cryptic variation is especially interesting to evolutionary biologists because it can result in selectable phenotypes when “released” by environmental or genetic factors. Currently, however, we have little idea of how variation is distributed between genes or over time in pattern formation processes. I am approaching this issue by studying how wing pattern formation can vary within the buckeye butterfly species Junonia coenia. In addition to surveying patterns of gene regulation over time, I am also developing a conceptual framework and analytical tools to make use of large data sets of spatial gene expression patterns. Regulation of wing pigment genes Many of the colors we perceive in butterfly wings are due to pigments. Several classes of pigments are found in butterfly wings including melanins, pterins, papiliochromes, and ommochromes. My current work is focused primarily on the ommochrome pigments - tryptophan-derived molecules that typically appear orange or red. Ommochromes are utilized throughout the insects as eye pigments, but have gained a novel function in wing coloration in brush-footed butterflies (Nymphalidae). These pigments provide a nice model for exploring how a complex biochemical process may be redeployed during evolution in a novel developmental context. I am studying the regulation of genes encoding transporters and enzymes required for ommochrome synthesis, and working to determine how the regulation of ommochrome genes is modulated by adaptive color pattern "switch genes" in polymorphic Heliconius butterflies. Notch signaling in butterfly wing pattern development Across the animal kingdom, the Notch signaling pathway is a fundamental component of pattern formation in many different contexts. Notch is a membrane-bound receptor molecule, and through interactions with ligands and other factors Notch is able to facilitate the formation of complex patterns during development. Previous gene expression studies in butterfly wings have implicated Notch in several pattern formation processes, including early eyespot determination and the arrangement of scale cells into spaced rows. I am also beginning to explore the role of Notch in determining butterfly wing shape. |
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| Publications | Reed, R.D., P.-H. Chen, and H.F. Nijhout (2007) Cryptic variation in butterfly eyespot development: the importance of sample size in gene expression studies. Evolution & Development 9: 2-9. | |
| Kapan, D.D., N.S. Flanagan, A. Tobler, R. Papa, R.D. Reed, J.A. Gonzalez, M.R. Restrepo, L. Martinez, K. Maldonado, C. Ritschoff, D.G. Heckel, and W.O. McMillan (2006) Localization of Müllerian mimicry genes on a dense linkage map of Heliconius erato. Genetics 173: 735-757. | ||
| Reed, R.D., and L.M. Nagy (2005) Evolutionary redeployment of a biosynthetic module: expression of eye pigment genes vermilion, cinnabar, and white in butterfly wing development. Evolution & Development 7: 301-311. | ||
| Reed, R.D. (2005) Gregarious oviposition in butterflies. Journal of the Lepidopterists’ Society 59: 40-43. | ||
| Reed, R.D., and M.S. Serfas (2004) Butterfly wing pattern evolution is associated with changes in a Notch/Distal-less temporal pattern formation process. Current Biology 14: 1159-1166. | ||
| Reed, R.D. (2004) Evidence for Notch-mediated lateral inhibition in organizing butterfly wing scales. Development Genes and Evolution 214: 43-46. | ||
| Reed, R.D. (2003) Gregarious oviposition and clutch size adjustment by a Heliconius butterfly. Biotropica 35: 555-559. | ||
| Caterino, M., R.D. Reed, M.M. Kuo, and F.A.H. Sperling (2001) A partitioned likelihood analysis of swallowtail butterfly phylogeny (Lepidoptera: Papilionidae). Systematic Biology 50: 106-127. | ||
| Reed, R.D., and F.A.H. Sperling (1999) The interaction of process partitions in phylogenetic analysis: an example from the swallowtail butterfly genus Papilio. Molecular Biology and Evolution 16: 286-297. | ||
| Grant | “Collaborative Grant: Molecular Basis of Mimicry in Heliconius Butterflies”. National Science Foundation DEB 0715140. 2007-2010. Principal Investigator. Collaborator: Owen McMillan (NCSU) | |
| Link to this profile | http://www.faculty.uci.edu/profile.cfm?faculty_id=5401 | |
| Last updated | 04/06/2007 | |