A model for the development of the hypothalamic-pituitary axis: transcribing the hypophysis

Mammalian organogenesis involves a sequential program to generate cells wit h specific fates and phenotypes from a common primordium, which is hypothes ized to be the consequence of regulated overlapping patterns of expression of specific sets of transcription factors in a precise spatiotemporal manne r. The hypothalamic-pituitary axis is critical for survival and homeostasis , controlling growth, reproduction, metabolism and behavior, and constitute s an ideal model in which to define the molecular markers to emergence of s pecific cell phenotypes from a common primordium, Development of the anteri or pituitary gland is controlled by sequential series of gradients of speci fic signaling molecules that, in turn, appear to coordinate the expression of specific combinations of transcription factor-encoding genes, many of wh ich as tissue-specific or tissue restricted factors that serially dictate c ell-type determination and terminal differentiation events that underlie th e differentiated cell phenotype. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.