Ca2+ signalling and early embryonic patterning during zebrafish development.
1. It has been proposed that Ca2+ signalling, in the form of pulses, waves and steady gradients, may play a crucial role in key pattern-forming events during early vertebrate development. 2. With reference to the embryo of the zebrafish (Danio rerio), herein we review the Ca2+ transients reported from the cleavage to segmentation periods. This time-window includes most of the major pattern-forming events of early development, which transform a single-cell zygote into a complex multicellular embryo with established primary germ layers and body axes. 3. Data are presented to support our proposal that intracellular Ca2+ waves are an essential feature of embryonic cytokinesis and that propagating intercellular Ca2+ waves (both long and short range) may play a crucial role in: (i) the establishment of the embryonic periderm and the coordination of cell movements during epiboly, convergence and extension; (ii) the establishment of the basic embryonic axes and germ layers; and (iii) definition of the morphological boundaries of specific tissue domains and embryonic structures, including future organ anlagen. 4. The potential downstream targets of these Ca2+ transients are also discussed, as well as how they may integrate with other pattern-forming signalling pathways known to modulate early developmental events.
Webb
Sarah E
SE
Department of Biology, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
Miller
Andrew L
AL
D000818:Animals; D036703:Blastula / Q000378:metabolism; D019521:Body Patterning; D020013:Calcium Signaling; D002465:Cell Movement; D002970:Cleavage Stage, Ovum / Q000378:metabolism; D048749:Cytokinesis; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000378:metabolism; D053595:Embryonic Stem Cells / Q000378:metabolism*; D005775:Gastrula / Q000378:metabolism; D013997:Time Factors; D015027:Zebrafish / Q000196:embryology* / Q000378:metabolism