Identification of the Transactivating Region of the Homeodomain Protein, Hex

Shinya Kasamatsu, Ayuko Sato, Taichi Yamamoto, Wee-Keong Vincent Keng, Hiroshi Yoshida, Yuka Yamazaki, Masafumi Shimoda, Jun Ichi Miyazaki, Tamio Noguchi

Research output: Journal article publicationJournal articleAcademic researchpeer-review

15 Citations (Scopus)


The homeodomain-containing protein Hex acts as an activator as well as a repressor of transcription in animals. While its repression domain has been mapped to the amino-terminal region, the activation domain has never been identified. Here, we show that the homeodomain and the acidic carboxyl-terminal region are necessary for full activation of the sodium-dependent bile acid cotransporter gene promoter in a cell type-independent manner, suggesting that the carboxyl-terminal region comprising residues 197 to 271 functions as the activation domain. In addition, we observed that a Hex mutant without this activation domain acts as a dominant-negative mutant as to the transactivating function of Hex.
Original languageEnglish
Pages (from-to)217-223
Number of pages7
JournalJournal of Biochemistry
Issue number2
Publication statusPublished - 1 Feb 2004
Externally publishedYes


  • Dominant-negative mutant
  • Hex
  • Sodium-dependent bile acid cotransporter
  • Transcriptional activator

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology

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