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Title: Interaction of the stress protein p8 with Jab1 is required for Jab1-dependent p27 nuclear-to-cytoplasm translocation

Abstract

p8 is an 80 amino-acid polypeptide identified because of its remarkable over-expression in the stressed pancreas. This protein, apparently devoid of enzymatic activity, is a powerful regulator of several intracellular pathways, suggesting that it has to interact with several molecular partners to modulate their activity. We used two-hybrid screening of a pre-transformed human testes cDNA library to identify some of these partners. One of them was the multifunctional protein Jab1, its interaction with p8 being confirmed by His{sub 6}-pull down and co-immunoprecipitation assays. In addition, we could show that the two proteins co-localized in the cell. Our functional data demonstrate that Jab1 requires direct interaction with p8 to induce the translocation of p27 from nucleus to cytoplasm and its subsequent degradation. Experiments showing that the knock-down of p8 expression results in a strong inhibition of Jab1 activity confirmed that the mechanism by which Jab1 promotes cell growth by decreasing p27 level is p8-dependent.

Authors:
 [1];  [1];  [2];  [3];  [1];  [1];  [4]
  1. INSERM U.624, Stress Cellulaire, 163 Avenue de Luminy, Case 915, Parc Scientifique et Technologique de Luminy, 13288 Marseille Cedex 9 (France)
  2. Departamento de Quimica Biologica, Ciudad Universitaria, Pabellon 2, Piso 4, 1428 Buenos Aires (Argentina)
  3. Experimental Pathology Department, IIBB-SCIC, IDIBAPS, Barcelona (Spain)
  4. INSERM U.624, Stress Cellulaire, 163 Avenue de Luminy, Case 915, Parc Scientifique et Technologique de Luminy, 13288 Marseille Cedex 9 (France). E-mail: iovanna@marseille.inserm.fr
Publication Date:
OSTI Identifier:
20795859
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 339; Journal Issue: 1; Other Information: DOI: 10.1016/j.bbrc.2005.11.018; PII: S0006-291X(05)02530-1; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; AMINO ACIDS; BIOLOGICAL STRESS; CELL CYCLE; CYTOPLASM; GROWTH; PANCREAS; POLYPEPTIDES; TESTES; TRANSLOCATION

Citation Formats

Malicet, Cedric, Hoffmeister, Albrecht, Moreno, Silvia, Closa, Daniel, Dagorn, Jean-Charles, Vasseur, Sophie, and Iovanna, Juan L. Interaction of the stress protein p8 with Jab1 is required for Jab1-dependent p27 nuclear-to-cytoplasm translocation. United States: N. p., 2006. Web. doi:10.1016/J.BBRC.2005.1.
Malicet, Cedric, Hoffmeister, Albrecht, Moreno, Silvia, Closa, Daniel, Dagorn, Jean-Charles, Vasseur, Sophie, & Iovanna, Juan L. Interaction of the stress protein p8 with Jab1 is required for Jab1-dependent p27 nuclear-to-cytoplasm translocation. United States. doi:10.1016/J.BBRC.2005.1.
Malicet, Cedric, Hoffmeister, Albrecht, Moreno, Silvia, Closa, Daniel, Dagorn, Jean-Charles, Vasseur, Sophie, and Iovanna, Juan L. 2006. "Interaction of the stress protein p8 with Jab1 is required for Jab1-dependent p27 nuclear-to-cytoplasm translocation". United States. doi:10.1016/J.BBRC.2005.1.
@article{osti_20795859,
title = {Interaction of the stress protein p8 with Jab1 is required for Jab1-dependent p27 nuclear-to-cytoplasm translocation},
author = {Malicet, Cedric and Hoffmeister, Albrecht and Moreno, Silvia and Closa, Daniel and Dagorn, Jean-Charles and Vasseur, Sophie and Iovanna, Juan L.},
abstractNote = {p8 is an 80 amino-acid polypeptide identified because of its remarkable over-expression in the stressed pancreas. This protein, apparently devoid of enzymatic activity, is a powerful regulator of several intracellular pathways, suggesting that it has to interact with several molecular partners to modulate their activity. We used two-hybrid screening of a pre-transformed human testes cDNA library to identify some of these partners. One of them was the multifunctional protein Jab1, its interaction with p8 being confirmed by His{sub 6}-pull down and co-immunoprecipitation assays. In addition, we could show that the two proteins co-localized in the cell. Our functional data demonstrate that Jab1 requires direct interaction with p8 to induce the translocation of p27 from nucleus to cytoplasm and its subsequent degradation. Experiments showing that the knock-down of p8 expression results in a strong inhibition of Jab1 activity confirmed that the mechanism by which Jab1 promotes cell growth by decreasing p27 level is p8-dependent.},
doi = {10.1016/J.BBRC.2005.1},
journal = {Biochemical and Biophysical Research Communications},
number = 1,
volume = 339,
place = {United States},
year = 2006,
month = 1
}
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