| David
McClay, Biology
Three areas of major focus of our work have been:
- on contributions of cell adhesion during two important
morphogenetic cell rearrangements in embryos. At
gastrulation a series of molecular changes in adherens
junctions and focal contacts occurs. Mesoderm cells
at ingression lose both of these adhesive structures
and invade the blastocoel. Later, endoderm cells
rearrange to form the archenteron, and in the process
both adherens junctions and focal contacts are altered.
We cloned cadherins, catenins, and integrins to
study these rapid morphogenetic changes that involve
an epithelial-mesenchymal cell conversion and convergent-extension
cell rearrangements. Our studies focus on the sequence
of events involved in that switch from an epithelial
cell to a mesenchymal cell, and in the sequence
through which the primitive gut is formed. Of importance,
Brachyury is involved in the morphogenetic switch
that permits archenteron invagination.
- to study a number of cell signaling events and
transcription factors in the sea urchin embryo that
specify endomesoderm. A gene regulatory network
was built based on data from cell- signaling and
specific transcription factor perturbations . ß-catenin
launches the specification and Notch later subdivides
the endomesoderm into mesoderm, plus endoderm (which
fails to receive the Notch signal). Current efforts
examine the mechanisms of these signals and other
molecular events that contribute to germ layer specification
- Morphogenesis and pattern formation of the neural
tube. We dissect neural tubes of mice as they form.
Current analysis examines the detailed molecular
adhesion transitions that assist in the folding
of the neural tube. The normal morphogenesis is
being compared to several mutants with a high penetrance
of neural tube defects.
Trainees participate in every aspect of the study. When
they rotate in the lab they have the choice of topic.
If they select my lab for research, topic choice is
theirs. Through journal clubs, seminars, and discussions
of the research, trainees acquire the knowledge and
experience necessary for an independent career.
See a picture of Dr. McClay's research
in our Gallery. |
