|
Hiroshi SASAKI, Ph. D. 
During
vertebrate embryogenesis, simply structured regions of undifferentiated
cells organize and cooperate to give rise to the anterior-posterior and
dorsal-ventral body axes, the neural tube and other embryonic structures
deriving from the three germ layers, following developmental patterns
that can be collectively summarized as the adult body plan. The embryo
is a hive of activity, including cell differentiation, proliferation and
migration, strictly regulated in both space and time by molecular signals
emitted by special regions of the embryo referred to as “signaling centers.”
These centers produce diffusible proteins that serve to regulate embryonic
development, guiding neighboring cell communities to take up the roles
they will play in the adult animal, or steering them away from inappropriate
fates.
Research
in our laboratory focuses on these signaling centers, especially those
of the mouse, as a model for studying the regulation of embryogenetic
processes. We focus particularly on the node and notochord, which are
of central importance in the formation of the early embryo. Focusing on
analyses of the roles played by the transcription factor Foxa2/HNF3β,
and defects in head development that result in a loss of function mutant
allele named headshrinker, we seek to determine the mechanisms
that establish and maintain signaling centers during development.
The functional analysis of signaling molecules, such as the protein Sonic hedgehog, in embryonic morphogenesis and the identification of novel molecules and systems in the regulation of signaling centers are also subjects of interest for current and future study.
