Pattern of Brachyury gene expression in starfish embryos resembles that of hemichordate embryos but not of sea urchin embryos

Mech Dev. 1999 Apr;82(1-2):185-9. doi: 10.1016/s0925-4773(99)00008-8.


Echinoderms, hemichordates and chordates are deuterostomes and share a number of developmental features. The Brachyury gene is responsible for formation of the notochord, the most defining feature of chordates, and thus may be a key to understanding the origin and evolution of the chordates. Previous studies have shown that the ascidian Brachyury (As-T and Ci-Bra) is expressed in the notochord and that a sea urchin Brachyury (HpTa) is expressed in the secondary mesenchyme founder cells. A recent study by [Tagawa et al. (1998)], however, revealed that a hemichordate Brachyury (PfBra) is expressed in a novel pattern in an archenteron invagination region and a stomodaeum invagination region in the gastrula. The present study demonstrated that the expression pattern of Brachyury (ApBra) of starfish embryos resembles that of PfBra in hemichordate embryos but not of HpTa in sea urchin embryos. Namely, ApBra is expressed in an archenteron invagination region and a stomodaeum invagination region.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Chordata, Nonvertebrate / embryology
  • Chordata, Nonvertebrate / genetics
  • DNA Primers / genetics
  • DNA-Binding Proteins / genetics*
  • Fetal Proteins*
  • Gene Expression Regulation, Developmental
  • Larva / genetics
  • Larva / growth & development
  • Molecular Sequence Data
  • Phylogeny
  • Sea Urchins / embryology
  • Sea Urchins / genetics
  • Species Specificity
  • Starfish / embryology*
  • Starfish / genetics*
  • Starfish / growth & development
  • T-Box Domain Proteins*
  • Transcription Factors / genetics*


  • DNA Primers
  • DNA-Binding Proteins
  • Fetal Proteins
  • T-Box Domain Proteins
  • Transcription Factors
  • Brachyury protein

Associated data

  • GENBANK/AB018527