De Robertis E M, Morita E A, Cho K W
Department of Biological Chemistry, University of California, Los Angeles 90024-1737.
Development. 1991 Jul;112(3):669-78. doi: 10.1242/dev.112.3.669.
We review here old experiments that defined the existence of morphogenetic gradient fields in vertebrate embryos. The rather abstract idea of cell fields of organ-forming potential has become less popular among modern developmental and molecular biologists. Results obtained with antibodies directed against homeodomain proteins suggest that gradient fields may indeed be visualized at the level of individual regulatory molecules in vertebrate embryos.
