Getting into shape: epidermal morphogenesis in Caenorhabditis elegans embryos

The change in shape of the C, elegans embryo from an ovoid bail of cells in to a worm-shaped larva is driven by three events within the cells of the hy podermis (epidermis): (1) intercalation of two rows of dorsal cells, (2) en closure of the ventral surface by hypodermis, and (3) elongation of the emb ryo. White the behavior of the hypodermal cells involved in each of these p rocesses differs dramatically, it is clear that F-actin and microtubules ha ve essential functions in each of these processes, whereas contraction of a ctomyosin structures appears to be involved specifically in elongation. Mol ecular analysis of these processes is revealing components specific to C. e legans as well as components found in other systems. Since C. elegans hypod ermal eel Is demonstrate dramatically different behaviors during intercalat ion, enclosure and elongation, the study of cytoskeletal dynamics in these processes may reveal both unique and conserved activities during distinct e pithelial morphogenetic movements. (C) 2001 John Wiley & Sons, Inc.