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Dev Genes Evol
2005 Aug 01;2158:383-92. doi: 10.1007/s00427-005-0486-9.
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From larval bodies to adult body plans: patterning the development of the presumptive adult ectoderm in the sea urchin larva.
Minsuk SB
,
Andrews ME
,
Raff RA
.
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Echinoderms are unique among bilaterians for their derived, nonbilateral adult body plan. Their radial symmetry emerges from the bilateral larval body plan by the establishment of a new axis, the adult oral-aboral axis, involving local mesoderm-ectoderm interactions. We examine the mechanisms underlying this transition in the direct-developing sea urchin Heliocidaris erythrogramma. Adult ectoderm arises from vestibular ectoderm in the left vegetal quadrant. Inductive signals from the left coelom are required for adult ectodermal development but not for initial vestibule formation. We surgically removed gastrula archenteron, making whole-ectoderm explants, left-, right-, and animal-half ectoderm explants, and recombinants of these explants with left coelom. Vestibule formation was analyzed morphologically and with radioactive in situ hybridization with HeET-1, an ectodermal marker. Whole ectodermal explants in the absence of coelom developed vestibules on the left side or ventrally but not on the right side, indicating that left-right polarity is ectoderm autonomous by the gastrula stage. However, right-half ectodermal explants robustly formed vestibules that went on to form adult structures when recombined with the left coelom, indicating that the right side retains vestibule-forming potential that is normally suppressed by signals from the left-side ectoderm. Animal-half explants formed vestibules only about half the time, demonstrating that animal-vegetal axis determination occurs earlier. However, when combined with the left coelom, animal-half ectoderm always formed a vestibule, indicating that the left coelom can induce vestibule formation. This suggests that although coelomic signals are not required for vestibule formation, they may play a role in coordinating the coelom-vestibule interaction that establishes the adult oral-aboral axis.
Aihara,
Left-right positioning of the adult rudiment in sea urchin larvae is directed by the right side.
2001, Pubmed,
Echinobase
Aihara,
Left-right positioning of the adult rudiment in sea urchin larvae is directed by the right side.
2001,
Pubmed
,
Echinobase
Angerer,
Patterning the sea urchin embryo: gene regulatory networks, signaling pathways, and cellular interactions.
2003,
Pubmed
,
Echinobase
Angerer,
Localization of mRNAs by in situ hybridization.
1991,
Pubmed
Brandhorst,
Molecular patterning along the sea urchin animal-vegetal axis.
2002,
Pubmed
,
Echinobase
Cameron,
Evolution of the chordate body plan: new insights from phylogenetic analyses of deuterostome phyla.
2000,
Pubmed
Davidson,
Origin of bilaterian body plans: evolution of developmental regulatory mechanisms.
1995,
Pubmed
Emlet,
Larval spicules, cilia, and symmetry as remnants of indirect development in the direct developing sea urchin Heliocidaris erythrogramma.
1995,
Pubmed
,
Echinobase
Ferkowicz,
Wnt gene expression in sea urchin development: heterochronies associated with the evolution of developmental mode.
2001,
Pubmed
,
Echinobase
Finnerty,
Origins of bilateral symmetry: Hox and dpp expression in a sea anemone.
2004,
Pubmed
Gerhart,
Inversion of the chordate body axis: are there alternatives?
2000,
Pubmed
Haag,
Isolation and characterization of three mRNAs enriched in embryos of the direct-developing sea urchin Heliocidaris erythrogramma: evolution of larval ectoderm.
1998,
Pubmed
,
Echinobase
Henry,
Progressive determination of cell fates along the dorsoventral axis in the sea urchin Heliocidaris erythrogramma.
1994,
Pubmed
,
Echinobase
Henry,
The dorsoventral axis is specified prior to first cleavage in the direct developing sea urchin Heliocidaris erythrogramma.
1990,
Pubmed
,
Echinobase
Henry,
Evolutionary change in the process of dorsoventral axis determination in the direct developing sea urchin, Heliocidaris erythrogramma.
1990,
Pubmed
,
Echinobase
Henry,
The development of dorsoventral and bilateral axial properties in sea urchin embryos.
1998,
Pubmed
,
Echinobase
Kauffman,
Patterning mechanisms in the evolution of derived developmental life histories: the role of Wnt signaling in axis formation of the direct-developing sea urchin Heliocidaris erythrogramma.
2003,
Pubmed
,
Echinobase
Kerr,
Bi-penta-bi-decaradial symmetry: A review of evolutionary and developmental trends in holothuroidea (echinodermata).
1999,
Pubmed
,
Echinobase
Minsuk,
Pattern formation in a pentameral animal: induction of early adult rudiment development in sea urchins.
2002,
Pubmed
,
Echinobase
Minsuk,
Co-option of an oral-aboral patterning mechanism to control left-right differentiation: the direct-developing sea urchin Heliocidaris erythrogramma is sinistralized, not ventralized, by NiCl2.
2005,
Pubmed
,
Echinobase
Nakano,
Larval stages of a living sea lily (stalked crinoid echinoderm).
2003,
Pubmed
,
Echinobase
Peterson,
Set-aside cells in maximal indirect development: evolutionary and developmental significance.
1997,
Pubmed
Peterson,
Bilaterian origins: significance of new experimental observations.
2000,
Pubmed
,
Echinobase
Peterson,
A comparative molecular approach to mesodermal patterning in basal deuterostomes: the expression pattern of Brachyury in the enteropneust hemichordate Ptychodera flava.
1999,
Pubmed
,
Echinobase
Peterson,
Expression pattern of Brachyury and Not in the sea urchin: comparative implications for the origins of mesoderm in the basal deuterostomes.
1999,
Pubmed
,
Echinobase
Popodi,
Hox genes in a pentameral animal.
2001,
Pubmed
,
Echinobase
Poznanski,
Epithelial cell wedging and neural trough formation are induced planarly in Xenopus, without persistent vertical interactions with mesoderm.
1997,
Pubmed
Sly,
Who came first--larvae or adults? origins of bilaterian metazoan larvae.
2003,
Pubmed
Summers,
The orientation of first cleavage in the sea urchin embryo, Lytechinus variegatus, does not specify the axes of bilateral symmetry.
1996,
Pubmed
,
Echinobase
Urata,
The development of the enteropneust hemichordate Balanoglossus misakiensis KUWANO.
2004,
Pubmed
Wray,
RAPID EVOLUTION OF GASTRULATION MECHANISMS IN A SEA URCHIN WITH LECITHOTROPHIC LARVAE.
1991,
Pubmed
,
Echinobase
Wray,
Novel origins of lineage founder cells in the direct-developing sea urchin Heliocidaris erythrogramma.
1990,
Pubmed
,
Echinobase
