Whole-Mount Immunolabeling of Embryos by Microinjection: Increased Detection Levels of Extracellular and Cell Surface Epitopes

A major conceptual breakthrough has occurred in the field of developmental morphogenesis in the past decade. It is now clear that molecular mechanisms at the external cell surface and within the surrounding extracellular matrix are fundamental to embryogenesis. Adhesion receptors, receptor tyrosine kinases, cell-cell recognition machinery, adhesion substrate molecules, and matrix-bound growth factors are all part of an instructive molecular language. Together these various kinds of molecules encode information that is displayed in a topographical manner. Understanding the physical and temporal distribution of these molecules is necessary if the morphogenetic code is to be deciphered.