Components of both major axial patterning systems of the Bilateria are differentially expressed along the primary axis of a 'radiate' animal, the anthozoan cnidarian Acropora millepora
- PMID: 16952346
- DOI: 10.1016/j.ydbio.2006.07.034
Components of both major axial patterning systems of the Bilateria are differentially expressed along the primary axis of a 'radiate' animal, the anthozoan cnidarian Acropora millepora
Abstract
Cnidarians are animals with a single (oral/aboral) overt body axis and with origins that nominally predate bilaterality. To better understand the evolution of axial patterning mechanisms, we characterized genes from the coral, Acropora millepora (Class Anthozoa) that are considered to be unambiguous markers of the bilaterian anterior/posterior and dorsal/ventral axes. Homologs of Otx/otd and Emx/ems, definitive anterior markers across the Bilateria, are expressed at opposite ends of the Acropora larva; otxA-Am initially around the blastopore and later preferentially toward the oral end in the ectoderm, and emx-Am predominantly in putative neurons in the aboral half of the planula larva, in a domain overlapping that of cnox-2Am, a Gsh/ind gene. The Acropora homologs of Pax-3/7, NKX2.1/vnd and Msx/msh are expressed in axially restricted and largely non-overlapping patterns in larval ectoderm. In Acropora, components of both the D/V and A/P patterning systems of bilateral animals are therefore expressed in regionally restricted patterns along the single overt body axis of the planula larva, and two 'anterior' markers are expressed at opposite ends of the axis. Thus, although some specific gene functions appear to be conserved between cnidarians and higher animals, no simple relationship exists between axial patterning systems in the two groups.
Similar articles
-
The origins of axial patterning in the metazoa: how old is bilateral symmetry?Int J Dev Biol. 2003;47(7-8):523-9. Int J Dev Biol. 2003. PMID: 14756328 Review.
-
Asymmetric expression of the BMP antagonists chordin and gremlin in the sea anemone Nematostella vectensis: implications for the evolution of axial patterning.Dev Biol. 2006 Aug 15;296(2):375-87. doi: 10.1016/j.ydbio.2006.06.003. Epub 2006 Jun 7. Dev Biol. 2006. PMID: 16828077
-
Axial patterning and diversification in the cnidaria predate the Hox system.Curr Biol. 2006 May 9;16(9):920-6. doi: 10.1016/j.cub.2006.03.036. Epub 2006 Mar 23. Curr Biol. 2006. PMID: 16563766
-
Gene structure and larval expression of cnox-2Am from the coral Acropora millepora.Dev Genes Evol. 2001 Jan;211(1):10-9. doi: 10.1007/s004270000112. Dev Genes Evol. 2001. PMID: 11277400
-
Coral development: from classical embryology to molecular control.Int J Dev Biol. 2002;46(4):671-8. Int J Dev Biol. 2002. PMID: 12141456 Review.
Cited by
-
The bilaterian head patterning gene six3/6 controls aboral domain development in a cnidarian.PLoS Biol. 2013;11(2):e1001488. doi: 10.1371/journal.pbio.1001488. Epub 2013 Feb 19. PLoS Biol. 2013. PMID: 23483856 Free PMC article.
-
The TALE face of Hox proteins in animal evolution.Front Genet. 2015 Aug 18;6:267. doi: 10.3389/fgene.2015.00267. eCollection 2015. Front Genet. 2015. PMID: 26347770 Free PMC article.
-
HeOtx expression in an indirectly developing polychaete correlates with gastrulation by invagination.Dev Genes Evol. 2007 May;217(5):373-84. doi: 10.1007/s00427-007-0150-7. Epub 2007 Apr 13. Dev Genes Evol. 2007. PMID: 17431669
-
Differential gene expression at coral settlement and metamorphosis--a subtractive hybridization study.PLoS One. 2011;6(10):e26411. doi: 10.1371/journal.pone.0026411. Epub 2011 Oct 31. PLoS One. 2011. PMID: 22065994 Free PMC article.
-
Are Hox genes ancestrally involved in axial patterning? Evidence from the hydrozoan Clytia hemisphaerica (Cnidaria).PLoS One. 2009;4(1):e4231. doi: 10.1371/journal.pone.0004231. Epub 2009 Jan 21. PLoS One. 2009. PMID: 19156208 Free PMC article.
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources