Formation of the Vertebrate Face Differentiation and Development

Abstract

Any attempt at understanding the problem of differentiation within the face is one of understanding the processes which manipulate cranial neural crest into the myriad of tissue types and forms this population of cells provides to the embryonic primordia of the craniofacial region. The differentiation of facial ectomesenchyme (neural crest-derived mesenchyme) is analyzed at 3 major developmental points: 1) The early commitment of neural crest prior to migration which will influence subsequent differentiation; 2) Induction and the inductive signal which initiates the differentiative cascade; and 3) The differentiative event itself, including factors which affect the processes of differentiation and growth and our current (limited) state of knowledge of the factors which control pattern formation during the differentiative process