Nuclear localization of I kappa B alpha promotes active transport of NF-kappa B from the nucleus to the cytoplasm.

I kappa B alpha tightly regulates the transcriptional activity of NF-kappa B by retaining it in the cytoplasm in an inactive form. In the present work, we report that I kappa B alpha, when expressed in the nuclear compartment, not only abrogates NF-kappa B/DNA interactions and NF-kappa B-dependent transcription, but ...
also transports NF-kappa B back to the cytoplasm. This function of I kappa B alpha is insured by a nuclear export sequence located in the C-terminal domain of I kappa B alpha and homologous to the previously described export signal found in HIV-1 Rev protein as well as in PKI (the inhibitor of the catalytic subunit of protein kinase A). Thus, inhibition of NF-kappa B/DNA binding and the consecutive efficient nuclear export of the transcription factor of I kappa B alpha could represent an important mechanism for the control of the expression of NF-kappa B-dependent genes.
Mesh Terms:
Amino Acid Sequence, Animals, Biological Transport, Active, Cell Nucleus, Cytoplasm, DNA-Binding Proteins, Female, HeLa Cells, Humans, I-kappa B Proteins, Molecular Sequence Data, NF-kappa B, Oocytes, Transcription, Genetic, Transfection, Xenopus laevis
J. Cell. Sci.
Date: Feb. 01, 1997
Download Curated Data For This Publication
159668
Switch View:
  • Interactions 2