Transcriptional regulation of Xbr-1a/Xvent-2 homeobox gene: analysis of its promoter region

Biochem Biophys Res Commun. 2002 Nov 15;298(5):815-23. doi: 10.1016/s0006-291x(02)02570-6.


Xvent homeobox proteins are induced by BMP-4 signaling and have been known to mediate many BMP-4 activities as key downstream transcriptional factors. In order to investigate the regulatory mode of Xvent transcription, we isolated genomic DNA of the Xbr-1a/Xvent-2 containing the promoter region responsive to BMP-4 signaling. The cis-acting elements located within the Xbr-1a/Xvent-2 promoter and the regulation modes by BMP-4 signaling were analyzed by serial deletion and site-directed mutagenesis experiments. The upstream -235bp of the promoter retained the full transcriptional activity and BMP-4-response when compared with the longest promoter construct. Further analysis indicated that two separated 15bp regions contained a strong positive element and BMP-4-response element. Site-directed mutagenesis of those regions suggests that those two regions cooperate for the promoter activity and BMP-4-response. Moreover, we found that the transcription factors, Oaz and PEBP2alphaA, were able to elicit additive effects with BMP-4 signaling on Xbr-1a/Xvent-2 reporter activities. These results indicate that transcriptional regulation of the Xbr-1a/Xvent-2 gene occurs in a complex mode through the cooperation of various transcription factors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Bone Morphogenetic Protein 4
  • Bone Morphogenetic Proteins / metabolism
  • DNA, Complementary / genetics
  • Eye Proteins / genetics*
  • Genes, Homeobox*
  • Homeodomain Proteins / genetics*
  • Molecular Sequence Data
  • Promoter Regions, Genetic*
  • Sequence Homology, Nucleic Acid
  • Signal Transduction
  • Transcription Factors*
  • Transcription, Genetic
  • Xenopus Proteins*
  • Xenopus laevis / embryology
  • Xenopus laevis / genetics*
  • Xenopus laevis / metabolism


  • Bone Morphogenetic Protein 4
  • Bone Morphogenetic Proteins
  • DNA, Complementary
  • Eye Proteins
  • Homeodomain Proteins
  • Transcription Factors
  • Xbr-1 protein, Xenopus
  • Xenopus Proteins
  • bmp4 protein, Xenopus
  • ventx2.1 protein, Xenopus