Plasma membrane-targeted Raf kinase activates NF-κB and human immunodeficiency virus type 1 replication in T lymphocytes

被引:48
作者
Flory, E
Weber, CK
Chen, PF
Hoffmeyer, A
Jassoy, C
Rapp, UR
机构
[1] Univ Wurzburg, Inst Med Strahlenkunde & Zellforsch, D-97078 Wurzburg, Germany
[2] Univ Wurzburg, Inst Virol & Immunbiol, D-97078 Wurzburg, Germany
关键词
D O I
10.1128/JVI.72.4.2788-2794.1998
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
Increasing evidence points to a role of the mitogenic Ras/Raf/MEK/ERK signaling cascade in regulation of human immunodeficiency virus type 1 (HIV-1) gene expression. Stimulation of elements of this pathway leads to transactivation of the HIV-1 promoter. In particular, the NF-kappa B motif in the HIV long terminal repeat (LTR) represents a Raf-responsive element in fibroblasts. Regulation of the Raf kinase in T cells differs from findings with a variety of cell lines that the catalytic domain of Raf (Raf(Delta 26-303)) shows no activity, In this study, we restored the activity of the kinase in T cells by fusing its catalytic domain to the CAAX motif (-Cx) of Ras,thus targeting the enzyme to the plasma membrane, Constitutive activity of Raf was demonstrated by phosphorylation of mitogen-activated protein kinase kinase (MEK) and endogenous mitogen-activated protein kinase 1/2 (ERK1/2) in A3.01 T cells transfected with Raf(Delta 26-303)-Cx. Membrane-targeted Raf also stimulates NF-kappa B, as judged by kappa B-dependent reporter assays and enhanced NF-kappa B p65 binding on band shift analysis. Moreover, we found that active Raf transactivates the HIVNL4-3 LTR in A3.01 T lymphocytes and that dominant negative Raf (C4) blocked 12-O-tetradecanoylphorbol-13-acetate induced transactivation. When cotransfected with infectious HIVNL4-3 DNA, membrane-targeted Raf induces viral replication up to 10-fold over basal levels, as determined by the release of newly synthesized p24(gag) protein, Our study clearly demonstrates that the activity of the catalytic domain of Raf in A3.01 T cells is dependent on its cellular localization, The functional consequences of active Raf in T lymphocytes include not only NF-kappa B activation and transactivation of the HIVNL4-3 LTR but also synthesis and release of HIV particles.
引用
收藏
页码:2788 / 2794
页数:7
相关论文
共 44 条
  • [21] PROTEIN KINASE-C-ALPHA ACTIVATES RAF-1 BY DIRECT PHOSPHORYLATION
    KOLCH, W
    HEIDECKER, G
    KOCHS, G
    HUMMEL, R
    VAHIDI, H
    MISCHAK, H
    FINKENZELLER, G
    MARME, D
    RAPP, UR
    [J]. NATURE, 1993, 364 (6434) : 249 - 252
  • [22] RAF-1 ACTIVATES MAP KINASE-KINASE
    KYRIAKIS, JM
    APP, H
    ZHANG, XF
    BANERJEE, P
    BRAUTIGAN, DL
    RAPP, UR
    AVRUCH, J
    [J]. NATURE, 1992, 358 (6385) : 417 - 421
  • [23] REQUIREMENT FOR RAS IN RAF ACTIVATION IS OVERCOME BY TARGETING RAF TO THE PLASMA-MEMBRANE
    LEEVERS, SJ
    PATERSON, HF
    MARSHALL, CJ
    [J]. NATURE, 1994, 369 (6479) : 411 - 414
  • [24] RAF-1 PROTEIN-KINASE ACTIVATES THE NF-KAPPA-B TRANSCRIPTION FACTOR BY DISSOCIATING THE CYTOPLASMIC NF-KAPPA-B-I-KAPPA-B COMPLEX
    LI, SF
    SEDIVY, JM
    [J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1993, 90 (20) : 9247 - 9251
  • [25] LOH C, 1994, J BIOL CHEM, V269, P8817
  • [26] RAS RECRUITS RAF-1 TO THE PLASMA-MEMBRANE FOR ACTIVATION BY TYROSINE PHOSPHORYLATION
    MARAIS, R
    LIGHT, Y
    PATERSON, HF
    MARSHALL, CJ
    [J]. EMBO JOURNAL, 1995, 14 (13) : 3136 - 3145
  • [27] The complexity of Raf-1 regulation
    Morrison, DK
    Cutler, RE
    [J]. CURRENT OPINION IN CELL BIOLOGY, 1997, 9 (02) : 174 - 179
  • [28] AN INDUCIBLE TRANSCRIPTION FACTOR ACTIVATES EXPRESSION OF HUMAN-IMMUNODEFICIENCY-VIRUS IN T-CELLS
    NABEL, G
    BALTIMORE, D
    [J]. NATURE, 1987, 326 (6114) : 711 - 713
  • [29] Naumann Ulrike, 1996, P203, DOI 10.1002/9783527615032.ch7
  • [30] RAF-1 IS REQUIRED FOR T-CELL IL2 PRODUCTION
    OWAKI, H
    VARMA, R
    GILLIS, B
    BRUDER, JT
    RAPP, UR
    DAVIS, LS
    GEPPERT, TD
    [J]. EMBO JOURNAL, 1993, 12 (11) : 4367 - 4373