Faculty Candidate Seminar - Deirdre Lyons

10/30/2015 - 12:15pm


DATE:          October 30th, Friday, 12:15 p.m.  

LOCATION:     Hubbs Hall 4500
SPEAKER:      Deirdre Lyons, Ph.D.
                        Duke University
TITLE:  Casting a wide net: capturing gene regulatory states that drive morphogenesis in marine

One of the most fascinating questions in biology remains how the diversity of organisms we
observe in the ocean came to be. For each generation, an animal first acquires its basic bodyplan
through the process of development; thus studying development will explain how animals
have different shapes, physiologies, and behaviors, each adapted to their unique environment.
In many cases, cell fate specification in animals is well-understood, thanks to the study of gene
regulatory networks (GRNs). GRNs describe the steps of cellular differentiation over time, with
a focus on regulatory connections between transcription factors and signaling molecules. My
research addresses aspects of development that are not well-understood, i.e., how a cell’s GRN
state launches events outside of the nucleus, for example complex cellular behaviors like
migration, cell shape change, or morphogenesis. I use two distantly related groups of marine
animals—sea urchins (echinoderms) and snails (gastropod molluscs)—because they are
tractable models for studying and manipulating development, and are representatives of the
deuterostome and lophotrochozoan branches of the animal tree, respectively. I will discuss my
recent work on the sea urchin endoskeleton, a biomineral that supports the pluteus larva during
its time in the plankton. I found that matrix metalloproteinases (MMPs) are necessary for
biomineralization and characterized the gene regulatory network that controls their expression.
I also developed the slipper snail, Crepidula, as a model for studying morphogenetic processes
during gastrulation, the period when the body-plan is established and germ layers (ectoderm,
endoderm, mesoderm) are segregated. Using advanced in vivo imaging techniques, I
uncovered a novel process of cell intercalation that closes the blastopore during gastrulation.
Future work will focus on building and comparing gene regulatory networks for cellular
processes in these species (e.g., biomineralization), and manipulating them using powerful
techniques, such as CRISPR genome editing. Such experiments will lead to a deeper
mechanistic understanding of how diverse animal body-plans are constructed, and uncover
fundamental mechanisms of animal development. Ultimately, this work serves as the jumpingoff
point for asking a wide range of questions about how cell biological processes are controlled, and have
influenced biological diversity, across deep evolutionary time scales.  

Faculty Host:  Greg Rouse  (grouse@ucsd.edu)
If you have an interest in meeting with the candidate, please contact lcosti@ucsd.edu.


For more information on this event, contact: 
Event Calendar: 
Hubbs Hall 4500