MORPHOGENETIC MOVEMENTS DURING AXOLOTL NEURAL-TUBE FORMATION TRACKED BY DIGITAL IMAGING

During neurulation in vertebrate embryos, epithelial cells of the neur al plate undergo complex morphogenetic movements that culminate in rol ling of the plate into a tube. Resolution of the determinants of this process requires an understanding of the precise movements of cells wi thin the epithelial sheet. A computer algorithm that allows automated tracking of epithelial cells visible in digitized video images is pres ented. It is used to quantify the displacement field associated with m orphogenetic movements in the axolotl (Anzbystoma mexicanum) neural pl ate during normal neural tube formation. Movements from lateral to med ial, axial elongations and area changes are calculated from the displa cement field data and plotted as functions of time. Regional and tempo ral differences are identified. The approach presented is suitable for analyzing a wide variety of morphogenetic movements.