An orthodenticle-related protein from Strongylocentrotus purpuratus

Dev Biol. 1995 Feb;167(2):517-28. doi: 10.1006/dbio.1995.1046.


Orthodenticle-related proteins function as regulators of head formation and other developmental events in flies and mice. Here, we characterize a cDNA clone encoding an orthodenticle-related protein from the sea urchin Strongylocentrotus purpuratus. The cDNA, termed SpOtx, has a highly conserved orthodenticle homeobox but otherwise diverges in sequence from its fly and mouse counterparts. Orthodenticle-related proteins bind with high affinity to DNA containing the sequence motif TAATCC/T. The S. purpuratus aboral ectoderm-specific Spec2a gene has several TAATCC/T sites in its control region, and we provide evidence, using bandshift analysis, that Spec2a may be target gene for SpOtx. Two SpOtx transcripts accumulate during embryogenesis, an early transcript whose level peaks at blastula stage and a late transcript accumulating to highest concentrations at gastrula stage. SpOtx transcripts were found initially in all cells of the cleaving embryo, but they gradually became restricted to oral ectoderm and endoderm cells. In contrast, SpOtx protein was found in nuclei of all cells at both blastula and pluteus stages. Our results suggest that SpOtx plays a role in the activation of the Spec2a gene and most likely has additional functions in the developing sea urchin embryo.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cloning, Molecular
  • DNA / metabolism
  • DNA, Complementary / genetics
  • Gene Expression Regulation, Developmental
  • Homeodomain Proteins / genetics*
  • Homeodomain Proteins / metabolism
  • Mice
  • Molecular Sequence Data
  • Nerve Tissue Proteins / genetics*
  • Nerve Tissue Proteins / metabolism
  • Phylogeny
  • Protein Binding
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Sea Urchins / embryology
  • Sea Urchins / genetics*
  • Sea Urchins / metabolism
  • Sequence Homology, Amino Acid


  • DNA, Complementary
  • Homeodomain Proteins
  • Nerve Tissue Proteins
  • RNA, Messenger
  • SpOtx protein, Strongylocentrotus purpuratus
  • DNA

Associated data

  • GENBANK/S76899