Molecular and Developmental Biology| Biological Sciences

Molecular and Developmental Biology

Faculty research interests in the area of molecular and developmental biology include evolutionary dervelopmental biology of vertebrates (Diaz Lab), developmental biology and cell signaling (Eivers Lab), molecular mechanisms in vertebrate development (Nissen Lab), and molecular regulatory mechanisms of development (Sharp Lab). An asterisk following a name in a publication citation indicates a student coauthor.

Evolutionary Developmental Biology of Vertebrates

		Contact:  Raul Diaz, Ph.D. Office:  ASCL 394, ext: 3-2077 Laboratory:  ASCL 309 E-mail:  [email protected]
		This image (data from digimorph.org) shows the unique skull anatomy present across chameleons where bones grow vertically away from the skull roof much like a tent, a unique architecture only seen in the extinct lineage of ceratopsid dinosaurs. Our lab aims to study how such unique morphologies develop and evolve and also examine how living organisms can provide us insight into better understanding species that have gone extinct.

Research Summary

My lab is interested in studying the diversity of body plans present across vertebrates (morphological disparity), but more specifically we are interested in the development and diversification of reptiles. Our sampling spans embryos produced in house as well as fieldwork both within and outside the USA. In addition, we employ a very broad array of classic and modern lab and genomic techniques to understand embryonic morphogenesis from a genetic to cellular and tissue level while also understanding how organisms interact with their environments by placing structural anatomy within the framework of biomechanics, ecology and phylogeny. Insights into the evolution of body plans can also come from understanding human diseases and lab based disease models, where anatomical changes associated with malformations are disadvantageous (or lethal) in some organisms, but are adaptive in other organisms and ecological contexts such as the cleft/split hands/feet of chameleons. This latter research area we have called Evo Devo Path and is also the study of “Hopeful Monsters.”

Developmental Biology and Cell Signaling

		Contact:  Edward Eivers, Ph.D. Office:  ASCL 392, ext: 3-2075 Laboratory:  ASCL 350, ext: 3-2071 E-mail:  [email protected]
		Fluorescent immunostaining of phosphorylated Mad in the dorsal most cells of a Drosophila blastoderm embryo. Phosphorylated Mad represents the cells which receive high levels of BMP signals. BMP target genes are strongly activated in this region.

Research Summary
My research lab investigates signaling crosstalk between the bone morphogenetic protein (BMP) and Wnt signaling pathways during Drosophila and Xenopus embryonic development. Both signaling pathways are evolutionarily conserved from flies to mammals and regulate a diverse range of biological events. These include stem cell maintenance, cell differentiation and organogenesis, while abnormal signaling of either pathway has strongly been linked to various forms of cancer. I am particularly interested in how the transcription factor Mad, which is required for both BMP and Wnt signaling, determines cell fate and differentiation during early tissue development.

Molecular Mechanisms in Vertebrate Development

		Contact:  Robert Nissen, Ph.D. Office:  ASCL 216, ext: 3-2309 Laboratory:  ASCL 210, ext: 3-2093 E-mail:  [email protected] Web:  /faculty/rnissen
		Example of a wild type zebrafish embryo at 28 hours. Zebrafish are used as a model organism for studying the molecular mechanisms of vertebrate development.

Research Summary
Our long-term goal is to understand the mechanisms by which an initially pluripotent cell becomes restricted to specific fates and subsequently how it is maintained in the differentiated state. Currently, our focus is aimed at revealing the roles that the Wdr68 and Dyrk1b proteins play in the Nodal signaling pathway using zebrafish as a model organism. Ultimately, we hope these studies will shed new and valuable light on the mechanisms driving cell specification and differentiation in vertebrates.

Molecular Regulatory Mechanisms of Development

		Contact:  Sandra Sharp, Ph.D. Office:  ASCL 316, ext: 3-2072 Laboratory:  ASCL 328, ext: 3-4820 E-mail:  [email protected] Web:  /faculty/ssharp
		AlexaFluor immuno-stained muscle fibers in a section of normal mouse hindlimb. Both cross and nearly longitudinal views are visible.

Research Summary
An important goal in biomedical research is to understand the molecular pathways and mechanisms that regulate development, particularly those that regulate the transition from cell proliferation to cell differentiation. Our model system is muscle development or myogenesis. We currently have two major projects supported by grant funding from the National Institutes of Health. The first uses whole animals and molecular studies to test the hypothesis that either the generally expressed tumor suppressor transcription factor p53 or the muscle-specific transcription factor MyoD must be expressed for successful completion of myogenesis in vivo. The second uses an ultra-high throughput ChIP-Seq approach to understand the regulatory mechanisms involved in controlling binding of MyoD to DNA as cells stop dividing and develop into muscle. We aspire to contribute to the understanding of the mechanisms that regulate normal differentiation in order to enable the development of successful medical approaches to both developmental disorders and cancer.

Note: ASCL = Wallis Annenberg Integrated Science Complex-Wing A (La Kretz Hall). When calling from off-campus, the area code and prefix for all telephone extensions is (323) 34X-XXXX.