The research interests and experience within this laboratory falls into the area broadly defined as evolution of developmental mechanisms. Our particular approach for understanding conserved and divergent properties of animal development is to compare architectural organization of gene regulatory networks (GRNs). GRN models consider not only the expression domains and function of many regulatory genes (mostly transcription factors), but importantly their inter-relationships. The construction of GRNs involves the use of cutting edge embryological and molecular biological technologies to study gene expression and to undertake gene perturbation, gene transfer and cis -regulatory analyses. Since our work is comparative these techniques must often be adapted for use in non-model organisms. The relationships between regulatory genes are portrayed as a network diagrams.    

We use a variety of marine invertebrates, particularly echinoderms, for our research. This is due largely to the fact that the most extensive GRN currently exists for the sea urchin embryo (see http://sugp.caltech.edu/endomes/) and the starfish has been shown to be an excellent comparative model. Also marine invertebrates represent the largest morphological diversity on the planet and present a wealth of opportunity to explore the association between development, phenotype and evolution.  

We use a comparative GRN method to answer questions such as:

1. What are conserved features of GRNs? These may be particular relationships of orthologous genes that can explain the preservation of phylotypic characters or may even represent developmental phenomena more widespread among the metazoa that are thus crucial for understanding animal development.  

2. How does the architecture of GRNs diverge with morphological differences in development and how did these architectural changes arise in evolution?

3. What are the similarities and differences that underlie the GRN of two independently evolving taxa that converge upon the same morphological outcome?

4. What is the cis -regulatory organization that underlies GRN structure and how has the cis regulatory logic evolved in conjunction with network architecture evolution?  

Selected Publications

Hinman, V.F., and Davidson, E.H. (2004). System-level Properties Revealed by a Gene Regulatory Network Analysis of Pregastrular Specification in Sea Urchins. In ' Gastrulation' . Ed. C. Stern. Cold Spring Harbor Laboratory Press. Cold Spring Habor.

Hinman, V.F., Nguyen, A.T., Cameron, R.A., and Davidson, E.H. (2003). Developmental gene regulatory network architecture across 500 MY of echinoderm evolution. Proceedings of the National Academy of Sciences of the United States of America, 100, 13356-13361.

Hinman, V.F., Nguyen, A.T., and Davidson, E.H. (2003). Expression and function of a starfish Otx ortholog, AmOtx: a conserved role for Otx proteins in endoderm development that predates divergence of the eleutherozoa. Mechanisms of Development 120, 1165-1176.

Hinman, V.F., O'Brien, E.K., Richards, G.S., and Degnan, B.M. (2003). Expression of anterior hox genes during larval development of the gastropod Haliotis asinina. Evolution and Development 5, 508-521.

Davidson, E.H., Rast, J.P., Oliveri, P., Ransick, A., Calestani, C., Yuh, C.H., Minokawa, T., Amore, G., Hinman, V., Arenas-Mena, C., Otim, O., Brown, C.T., Livi, C.B., Lee, P.Y., Revilla, R., Rust, A.G., Pan, Z.J., Schilstra, M.J., Clarke, P.J.C., Arnone, M.I., Rowen, L., Cameron, R.A., McClay, D.R., Hood, L., and Bolouri, H. (2002). A genomic regulatory network for development. Science 295, 1669-1678.

Hinman, V.F., and Degnan, B.M. (2000). Retinoic acid perturbs Otx gene expression in the ascidian pharynx. Development Genes and Evolution 210, 129-139.