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. |
