IκBα and p65 Regulate the Cytoplasmic Shuttling of Nuclear Corepressors: Cross-talk between Notch and NFκB Pathways

Notch and NFκB pathways are key regulators of numerous cellular events such as proliferation, differentiation, or apoptosis. In both pathways, association of effector proteins with nuclear corepressors is responsible for their negative regulation. We have previously described that expression of a p65-NFκB mutant that lacks the transactivation domain (p65ΔTA) induces cytoplasmic translocation of N-CoR leading to a positive regulation of different promoters. Now, we show that cytoplasmic sequestration of p65 by IκBα is sufficient to both translocate nuclear corepressors SMRT/N-CoR to the cytoplasm and upregulate transcription of Notch-dependent genes. Moreover, p65 and IκBα are able to directly bind SMRT, and this interaction can be inhibited in a dose-dependent manner by the CREB binding protein (CBP) coactivator and after TNF-α treatment, suggesting that p65 acetylation is modulating this interaction. In agreement with this, TNF-α treatment results in downregulation of the Hes1 gene. Finally, we present evidence on how this mechanism may influence cell differentiation in the 32D myeloid progenitor system.

[1]  J. Licht,et al.  AML-1/ETO fusion protein is a dominant negative inhibitor of transcriptional repression by the promyelocytic leukemia zinc finger protein. , 2000, Blood.

[2]  J. Leiden,et al.  NF-κB Is Required for the Positive Selection of CD8+ Thymocytes1 , 2000, The Journal of Immunology.

[3]  H. Weintraub,et al.  The intracellular domain of mouse Notch: a constitutively activated repressor of myogenesis directed at the basic helix-loop-helix region of MyoD. , 1994, Development.

[4]  J. Laborda,et al.  T cell leukemia-associated human Notch/translocation-associated Notch homologue has I kappa B-like activity and physically interacts with nuclear factor-kappa B proteins in T cells , 1996, The Journal of experimental medicine.

[5]  David Baltimore,et al.  Embryonic lethality and liver degeneration in mice lacking the RelA component of NF-κB , 1995, Nature.

[6]  M. Downes,et al.  The nuclear receptor corepressor N-CoR regulates differentiation: N-CoR directly interacts with MyoD. , 1999, Molecular endocrinology.

[7]  L. Miele,et al.  Human Notch-1 Inhibits NF-κB Activity in the Nucleus Through a Direct Interaction Involving a Novel Domain1 , 2001, The Journal of Immunology.

[8]  J. Greenberger,et al.  Demonstration of permanent factor-dependent multipotential (erythroid/neutrophil/basophil) hematopoietic progenitor cell lines. , 1983, Proceedings of the National Academy of Sciences of the United States of America.

[9]  M. Karin,et al.  Mapping of the inducible IkappaB phosphorylation sites that signal its ubiquitination and degradation , 1996, Molecular and cellular biology.

[10]  M. Privalsky,et al.  The SMRT Corepressor Is Regulated by a MEK-1 Kinase Pathway: Inhibition of Corepressor Function Is Associated with SMRT Phosphorylation and Nuclear Export , 2000, Molecular and Cellular Biology.

[11]  T. Hope,et al.  An N‐terminal nuclear export signal is required for the nucleocytoplasmic shuttling of IκBα , 1999 .

[12]  Sandy D. Westerheide,et al.  The p65 (RelA) Subunit of NF-κB Interacts with the Histone Deacetylase (HDAC) Corepressors HDAC1 and HDAC2 To Negatively Regulate Gene Expression , 2001, Molecular and Cellular Biology.

[13]  T. Yamagata,et al.  Notch1 inhibits differentiation of hematopoietic cells by sustaining GATA-2 expression. , 2001, Blood.

[14]  M. Pazin,et al.  What's Up and Down with Histone Deacetylation and Transcription? , 1997, Cell.

[15]  A. Bigas,et al.  Notch as a mediator of cell fate determination in hematopoiesis: evidence and speculation. , 1999, Blood.

[16]  T. Gilmore,et al.  Control of apoptosis by Rel/NF-κB transcription factors , 1999, Oncogene.

[17]  J. Hsieh,et al.  A Role for SKIP in EBNA2 Activation of CBF1-Repressed Promoters , 2000, Journal of Virology.

[18]  C. Glass,et al.  Coactivator and corepressor complexes in nuclear receptor function. , 1999, Current opinion in genetics & development.

[19]  P. Chomczyński,et al.  Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. , 1987, Analytical biochemistry.

[20]  C. Leow,et al.  Notch receptors, partners and regulators: from conserved domains to powerful functions. , 1998, Current topics in microbiology and immunology.

[21]  I. Bernstein,et al.  Inhibition of granulocytic differentiation by mNotch1. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[22]  L. Espinosa,et al.  Phosphorylation of Ser2078 Modulates the Notch2 Function in 32D Cell Differentiation* , 2001, The Journal of Biological Chemistry.

[23]  M. Bevan,et al.  Notch1 signaling promotes the maturation of CD4 and CD8 SP thymocytes. , 2000, Immunity.

[24]  A. Strasser,et al.  Mice lacking the c-rel proto-oncogene exhibit defects in lymphocyte proliferation, humoral immunity, and interleukin-2 expression. , 1995, Genes & development.

[25]  S. Miyamoto,et al.  Postrepression Activation of NF-κB Requires the Amino-Terminal Nuclear Export Signal Specific to IκBα , 2001, Molecular and Cellular Biology.

[26]  T. Kadesch,et al.  Notch signaling: a dance of proteins changing partners. , 2000, Experimental cell research.

[27]  E. Harhaj,et al.  Regulation of RelA Subcellular Localization by a Putative Nuclear Export Signal and p50 , 1999, Molecular and Cellular Biology.

[28]  G. Weinmaster,et al.  An Activated Form of Notch Influences the Choice between CD4 and CD8 T Cell Lineages , 1996, Cell.

[29]  P. Delmas,et al.  Osteoclast spreading kinetics are correlated with an oscillatory activation of a calcium-dependent potassium current , 2002, Journal of Cell Science.

[30]  I. Bernstein,et al.  Monocytes express high amounts of Notch and undergo cytokine specific apoptosis following interaction with the Notch ligand, Delta-1. , 2000, Blood.

[31]  Xiang-Jiao Yang,et al.  Cell Signaling Switches HOX-PBX Complexes from Repressors to Activators of Transcription Mediated by Histone Deacetylases and Histone Acetyltransferases , 2000, Molecular and Cellular Biology.

[32]  M. Palacín,et al.  Insulin-like Growth Factor-II, Phosphatidylinositol 3-Kinase, Nuclear Factor-κB and Inducible Nitric-oxide Synthase Define a Common Myogenic Signaling Pathway* , 1999, The Journal of Biological Chemistry.

[33]  J. Cheong,et al.  Silencing Mediator of Retinoic Acid and Thyroid Hormone Receptors, as a Novel Transcriptional Corepressor Molecule of Activating Protein-1, Nuclear Factor-κB, and Serum Response Factor* , 2000, The Journal of Biological Chemistry.

[34]  S. Akira,et al.  Iκb Kinase α Is Essential for Mature B Cell Development and Function , 2001, The Journal of experimental medicine.

[35]  Marty W. Mayo,et al.  Akt Stimulates the Transactivation Potential of the RelA/p65 Subunit of NF-κB through Utilization of the IκB Kinase and Activation of the Mitogen-activated Protein Kinase p38* , 2001, The Journal of Biological Chemistry.

[36]  A. Bigas,et al.  Notch1 and Notch2 Inhibit Myeloid Differentiation in Response to Different Cytokines , 1998, Molecular and Cellular Biology.

[37]  R. Evans,et al.  A histone deacetylase corepressor complex regulates the Notch signal transduction pathway. , 1998, Genes & development.

[38]  G. Stark,et al.  Distinct Roles of the IκB Kinase α and β Subunits in Liberating Nuclear Factor κB (NF-κB) from IκB and in Phosphorylating the p65 Subunit of NF-κB* , 2001, The Journal of Biological Chemistry.

[39]  Minoru Yoshida,et al.  A nuclear export signal in the N-terminal regulatory domain of IκBα controls cytoplasmic localization of inactive NF-κB/IκBα complexes , 2000 .

[40]  C. Glass,et al.  Molecular determinants of nuclear receptor-corepressor interaction. , 1999, Genes & development.

[41]  A. Garcı́a-Bellido,et al.  Notch signaling directly controls cell proliferation in the Drosophila wing disc. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[42]  J. Hsieh,et al.  CIR, a corepressor linking the DNA binding factor CBF1 to the histone deacetylase complex. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[43]  Christel Brou,et al.  Signalling downstream of activated mammalian Notch , 1995, Nature.

[44]  Hui Li,et al.  SMRTe Inhibits MEF2C Transcriptional Activation by Targeting HDAC4 and 5 to Nuclear Domains* , 2001, The Journal of Biological Chemistry.

[45]  M. Boothby,et al.  Perturbation of the T Lymphocyte Lineage In Transgenic Mice Expressing a Constitutive Repressor of Nuclear Factor (NF)-κB , 1997, The Journal of experimental medicine.

[46]  A. Porter,et al.  NF-κB/Rel Proteins Are Required for Neuronal Differentiation of SH-SY5Y Neuroblastoma Cells* , 1999, The Journal of Biological Chemistry.

[47]  Y. Nagamine,et al.  UV Irradiation Induces the Murine Urokinase-Type Plasminogen Activator Gene via the c-Jun N-Terminal Kinase Signaling Pathway: Requirement of an AP1 Enhancer Element , 1998, Molecular and Cellular Biology.

[48]  S. Hayward,et al.  Nuclear Localization of CBF1 Is Regulated by Interactions with the SMRT Corepressor Complex , 2001, Molecular and Cellular Biology.

[49]  Eric Verdin,et al.  Duration of Nuclear NF-κB Action Regulated by Reversible Acetylation , 2001, Science.

[50]  S. Ghosh,et al.  Phosphorylation of NF-kappa B p65 by PKA stimulates transcriptional activity by promoting a novel bivalent interaction with the coactivator CBP/p300. , 1998, Molecular cell.

[51]  Céline Gélinas,et al.  Rel/NF‐κB can trigger the Notch signaling pathway by inducing the expression of Jagged1, a ligand for Notch receptors , 1999, The EMBO journal.

[52]  K. Knudtson,et al.  The p38 mitogen-activated protein kinase is required for NF-kappaB-dependent gene expression. The role of TATA-binding protein (TBP). , 1999, The Journal of biological chemistry.

[53]  W. Pear,et al.  Cutting edge: protective effects of notch-1 on TCR-induced apoptosis. , 1999, Journal of immunology.

[54]  Eva E. Qwarnstrom,et al.  Dynamic Shuttling of Nuclear Factor κB between the Nucleus and Cytoplasm as a Consequence of Inhibitor Dissociation* , 2000, The Journal of Biological Chemistry.

[55]  S. Minoguchi,et al.  Delta-induced Notch Signaling Mediated by RBP-J Inhibits MyoD Expression and Myogenesis* , 1999, The Journal of Biological Chemistry.

[56]  Christopher K. Glass,et al.  Exchange of N-CoR Corepressor and Tip60 Coactivator Complexes Links Gene Expression by NF-κB and β-Amyloid Precursor Protein , 2002, Cell.

[57]  A. Israël,et al.  Delta-1 Activation of Notch-1 Signaling Results inHES-1 Transactivation , 1998, Molecular and Cellular Biology.

[58]  L. Miele,et al.  Notch‐1 inhibits apoptosis in murine erythroleukemia cells and is necessary for differentiation induced by hybrid polar compounds , 1999, Journal of cellular biochemistry.

[59]  C. Y. Wang,et al.  NF-kappaB-induced loss of MyoD messenger RNA: possible role in muscle decay and cachexia. , 2000, Science.

[60]  G. McKnight,et al.  Mutations in the catalytic subunit of cAMP-dependent protein kinase result in unregulated biological activity. , 1992, Proceedings of the National Academy of Sciences of the United States of America.

[61]  J. Sklar,et al.  Notch1-induced delay of human hematopoietic progenitor cell differentiation is associated with altered cell cycle kinetics. , 1999, Blood.

[62]  L. Espinosa,et al.  p65-NFkappaB synergizes with Notch to activate transcription by triggering cytoplasmic translocation of the nuclear receptor corepressor N-CoR. , 2002, Journal of cell science.

[63]  M. Karin,et al.  Phosphorylation meets ubiquitination: the control of NF-[kappa]B activity. , 2000, Annual review of immunology.