The development of specific cell types during mammalian organogenesis appears to involve molecular strategies analogous to those utilized for initial patterning in Drosophila development, involving gradients of signaling molecules that generate overlapping patterns of transcription factors. We are using mouse genetics and in vitro systems to study several steps of mammalian organogenesis, with special focus on pituitary organogenesis. The pituitary gland with its well characterized cell phenotypes serves critical homeostatic functions by regulating key endocrine organ targets in response to signals from brain and periphery.
In particular, we are interested in the following questions:
What are the molecular events that specify the site of organ initiation within a morphologically indistinguishable region?
How do transient signaling gradients establish the transcriptional programs that dictate cell type specification and provide the molecular memory in vivo to ‘lock in’ the pituitary cell phenotypes?
We have recently begun to define the transcriptional programs that mediate the signal induced positional determination events during pituitary organogenesis that will provide us with the molecular framework for our future research.