T-box and homeobox genes from the ctenophore Pleurobrachia pileus: comparison of Brachyury, Tbx2/3 and Tlx in basal metazoans and bilaterians

FEBS Lett. 2005 Sep 12;579(22):5024-8. doi: 10.1016/j.febslet.2005.08.008.

Abstract

Most animals are classified as Bilateria and only four phyla are still extant as outgroups, namely Porifera, Placozoa, Cnidaria and Ctenophora. These non-bilaterians were not considered to have a mesoderm and hence mesoderm-specific genes. However, the T-box gene Brachyury could be isolated from sponges, placozoans and cnidarians. Here, we describe the first Brachyury and a Tbx2/3 homologue from a ctenophore. In addition, analysing T-box and homeobox genes under comparable conditions in all four basal phyla lead to the discovery of novel T-box genes in sponges and cnidarians and a Tlx homeobox gene in the ctenophore Pleurobrachia pileus. The conservation of the T-box and the homeobox genes suggest that distinct subfamilies with different roles in bilaterians were already split in non-bilaterians.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Ctenophora / genetics*
  • Evolution, Molecular
  • Fetal Proteins / genetics*
  • Genes, Homeobox*
  • Humans
  • Molecular Sequence Data
  • Multigene Family
  • Phylogeny
  • Sequence Alignment
  • T-Box Domain Proteins / classification
  • T-Box Domain Proteins / genetics*

Substances

  • Fetal Proteins
  • T-Box Domain Protein 2
  • T-Box Domain Proteins
  • Brachyury protein