EKLF/KLF1 is ubiquitinated in vivo and its stability is regulated by activation domain sequences through the 26S proteasome

FEBS Lett. 2006 Apr 17;580(9):2285-93. doi: 10.1016/j.febslet.2006.03.039. Epub 2006 Mar 24.

Abstract

Erythroid Krüppel-like factor (EKLF/KLF1) is an erythroid specific, C(2)H(2) zinc finger transcription factor that is essential for the proper chromatin structure and expression of the adult beta-globin gene. Herein, we determine that 26S proteasome inhibitors lead to an accumulation of EKLF protein in murine erythroleukemia (MEL) cells. In addition, EKLF half-life in both MEL cells (<3h) and fetal liver cells (between 6 and 9h) is stabilized in the presence of these inhibitors. EKLF is ubiquitinated in vivo, however its modification does not rely on a particular internal lysine. Finally, EKLF contains two PEST sequences within its N-terminus that have no effect on the ability of EKLF to be ubiquitinated but contribute to its destabilization.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Amino Acid Motifs / genetics
  • Animals
  • COS Cells
  • Chlorocebus aethiops
  • Chromatin / metabolism
  • Fetus / metabolism
  • Gene Expression Regulation, Developmental / physiology
  • Globins / biosynthesis
  • Humans
  • Kruppel-Like Transcription Factors / genetics
  • Kruppel-Like Transcription Factors / metabolism*
  • Liver / metabolism
  • Lysine / genetics
  • Lysine / metabolism
  • Mice
  • Proteasome Endopeptidase Complex / metabolism*
  • Protein Processing, Post-Translational / physiology*
  • Ubiquitin / genetics
  • Ubiquitin / metabolism*

Substances

  • Chromatin
  • Kruppel-Like Transcription Factors
  • Ubiquitin
  • erythroid Kruppel-like factor
  • Globins
  • Proteasome Endopeptidase Complex
  • ATP dependent 26S protease
  • Lysine