SpRunt-1, a new member of the runt domain family of transcription factors, is a positive regulator of the aboral ectoderm-specific CyIIIA gene in sea urchin embryos

Dev Biol. 1996 Feb 25;174(1):43-54. doi: 10.1006/dbio.1996.0050.


In this paper we present a structural and functional characterization of a new sea urchin embryo transcription factor, SpRunt-1. This factor was isolated by means of its specific interaction with a cis-regulatory target site of the CyIIIa gene. Here we show that this target site, the P7I site, is required for normal embryonic activation of CyIIIa x CAT reporter gene constructs. An oligonucleotide affinity column bearing the P7I target site purifies a 21-kDa polypeptide from blastula-stage nuclear extracts, and the amino acid sequence obtained from this polypeptide was used to generate a nucleic acid probe with which the corresponding cDNA was cloned. The cDNA encodes an approximately 60-kDa protein, SpRunt-1, which includes a "runt domain" that is closely homologous to those of Drosophila and mammalian runt domain transcription factors. RNA and genomic blots show that SpRunt-1 is represented by a single embryonic transcript, encoded by one of possibly two runt-domain-containing genes. By RNA probe protection we found that transcripts of SpRunt-1 increase in concentration dramatically after the blastula stage of development, suggesting that the up-regulation of CyIIIa that occurs after blastula stage is a function of zygotically transcribed SpRunt-1. These results are discussed with reference to known features of the runt domain family of transcription factors.

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

  • Actins / genetics*
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / physiology
  • Gene Expression Regulation, Developmental
  • Humans
  • Mice
  • Molecular Sequence Data
  • Oligonucleotide Probes / chemistry
  • RNA, Messenger / genetics
  • Regulatory Sequences, Nucleic Acid
  • Sea Urchins / embryology*
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Transcription Factors / chemistry
  • Transcription Factors / physiology*
  • Transcription, Genetic


  • Actins
  • DNA-Binding Proteins
  • Oligonucleotide Probes
  • RNA, Messenger
  • SpRunt-1 protein, Strongylocentrotus purpuratus
  • Transcription Factors

Associated data

  • GENBANK/U41512