Specifying positional information in the embryo: looking beyond morphogens.
Concentration gradients of small diffusible molecules called morphogens are key regulators of development, specifying position during pattern formation in the embryo. It is now becoming clear that additional or alternative mechanisms involving interactions among cells are also crucial for positional specification.
Kerszberg
Michel
M
Université Pierre et Marie Curie-Paris 6, UMR7138 CNRS, 75005 Paris, France. mkersz@ccr.jussieu.fr
Wolpert
Lewis
L
D000818:Animals; D019521:Body Patterning; D004331:Drosophila melanogaster / Q000196:embryology*; D004625:Embryo, Nonmammalian / Q000378:metabolism*