The Flt3 internal tandem duplication mutant inhibits the function of transcriptional repressors by blocking interactions with SMRT

Shinichiro Takahashi, Melanie J. McConnell, Hideo Harigae, Mitsuo Kaku, Takeshi Sasaki, Ari M. Melnick, Jonathan D. Licht

研究成果: Article査読

29 被引用数 (Scopus)

抄録

Fms-like tyrosine kinase 3 (Flt3) is a type III receptor tyrosine kinase (RTK). Between 20% and 30% of acute myeloid leukemia (AML) patients have either an internal tandem duplication (ITD) of the juxtamembrane region or a point mutation of the Flt3 receptor leading to the constitutive activation of downstream signaling pathways and aberrant cell growth. The silencing mediator of retinoic and thyroid hormone receptors (SMRT) corepressor mediates transcriptional repression by interacting with transcription factors such as the promyelocytic leukemia zinc finger (PLZF) protein. Previous reports indicate that SMRT interaction with transcription factors can be disrupted by phosphorylation through activation of RTK pathways. We report here that the Flt3-ITD interferes with the transcriptional and biologic action of the PLZF transcriptional repressor. In the presence of Flt3-ITD, PLZF-SMRT interaction was reduced, transcriptional repression by PLZF was inhibited, and PLZF-mediated growth suppression of leukemia cells was partially blocked. Furthermore, overexpression of Flt3-ITD led to a partial relocalization of SMRT protein from the nucleus to the cytoplasm. Nuclear export was dependent on the SMRT receptor interaction domain (RID), and Flt3-ITD enhances the binding of nuclear-cytoplasm shuttling protein nuclear factor-κB-p65 (NFκB-p65) to this region. These data suggest that activating mutations of Flt3 may disrupt transcriptional repressor function resulting in aberrant gene regulation and abnormal leukemia cell growth.

本文言語English
ページ(範囲)4650-4658
ページ数9
ジャーナルBlood
103
12
DOI
出版ステータスPublished - 2004 6 15

ASJC Scopus subject areas

  • 生化学
  • 免疫学
  • 血液学
  • 細胞生物学

フィンガープリント

「The Flt3 internal tandem duplication mutant inhibits the function of transcriptional repressors by blocking interactions with SMRT」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル