Pathogenic bacteria target NEDD8-conjugated cullins to hijack host-cell signaling pathways.
Pathogenic bacteria target NEDD8-conjugated cullins to hijack host-cell signaling pathways.
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DOI：
10.1371/journal.ppat.1001128
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发表时间：
2010-09-30
期刊：
影响因子：
6.7
通讯作者：
Oswald E
中科院分区：
文献类型：
--
作者：
Jubelin G;Taieb F;Duda DM;Hsu Y;Samba-Louaka A;Nobe R;Penary M;Watrin C;Nougayrède JP;Schulman BA;Stebbins CE;Oswald E
周期抑制因子（Cif）是由从脊椎动物和无脊椎动物中分离出来的致病菌产生的，它属于干扰真核细胞周期的环状调节蛋白分子家族。Cif通过诱导周期蛋白依赖性激酶抑制剂p21waf1和p27kip1的稳定，阻断细胞周期在G1/S和G2/M的转变。通过酵母双杂交筛选，我们确定了泛素样蛋白NEDD8作为Cif的靶标。Cif在宿主细胞核中与NEDD8共区隔，诱导了NEDD8共轭cullins的积累。这种积累发生在细胞感染后的早期，并与p21和p27相关。共免疫沉淀显示Cif通过结合cullins的1、2、3、4A和4B亚基的类木素化形式与cullins - ring泛素连接酶复合物（CRLs）相互作用。通过体外泛素化实验，我们证明Cif直接抑制了类木化cul1相关泛素连接酶的活性。与这种抑制作用以及Cif与几种类木化cullins的相互作用相一致，我们进一步观察到Cif调节了各种CRL靶点的细胞半衰期，这可能有助于多种细菌的致病潜力。在细菌病原体用来感染和操纵宿主的毒力因子库中，环调节蛋白是一种越来越多的干扰真核细胞周期的细菌毒素。Cif是一种由哺乳动物和无脊椎致病菌产生的环调节蛋白。Cif通过诱导细胞周期进程的两种调节因子的积累来阻断宿主细胞周期：周期蛋白依赖性激酶抑制剂p21和p27。为了破译Cif的作用模式，我们进行了酵母双杂交筛选。我们发现Cif与NEDD8结合，并在感染后早期诱导泛素化cullins的积累。Cullins是cullin-RING泛素连接酶（CRLs）的支架组分，它使蛋白质泛素化并靶向它们被26S蛋白酶体降解。我们证明Cif直接抑制这些crl的泛素连接酶活性，从而靶向p21和p27进行泛素依赖性降解。以NEDD8为靶点是细菌病原体调节宿主细胞功能的一种新策略。通过抑制最突出的一类泛素连接酶，Cif控制了一系列关键调节因子的稳定性，不仅影响细胞周期进程，还影响许多细胞和生物过程，如免疫、发育、转录和细胞信号传导。
The cycle inhibiting factors (Cif), produced by pathogenic bacteria isolated from vertebrates and invertebrates, belong to a family of molecules called cyclomodulins that interfere with the eukaryotic cell cycle. Cif blocks the cell cycle at both the G1/S and G2/M transitions by inducing the stabilization of cyclin-dependent kinase inhibitors p21waf1 and p27kip1. Using yeast two-hybrid screens, we identified the ubiquitin-like protein NEDD8 as a target of Cif. Cif co-compartmentalized with NEDD8 in the host cell nucleus and induced accumulation of NEDD8-conjugated cullins. This accumulation occurred early after cell infection and correlated with that of p21 and p27. Co-immunoprecipitation revealed that Cif interacted with cullin-RING ubiquitin ligase complexes (CRLs) through binding with the neddylated forms of cullins 1, 2, 3, 4A and 4B subunits of CRL. Using an in vitro ubiquitylation assay, we demonstrate that Cif directly inhibits the neddylated CUL1-associated ubiquitin ligase activity. Consistent with this inhibition and the interaction of Cif with several neddylated cullins, we further observed that Cif modulates the cellular half-lives of various CRL targets, which might contribute to the pathogenic potential of diverse bacteria. Among the arsenal of virulence factors used by bacterial pathogens to infect and manipulate their hosts, cyclomodulins are a growing family of bacterial toxins that interfere with the eukaryotic cell-cycle. Cif is one of these cyclomodulins produced by both mammalian and invertebrate pathogenic bacteria. Cif blocks the host cell cycle by inducing the accumulation of two regulators of cell cycle progression: the cyclin-dependent kinase inhibitors p21 and p27. To decipher the mode of action of Cif, we performed yeast two-hybrid screenings. We show that Cif binds to NEDD8 and induce accumulation of neddylated cullins early after infection. Cullins are scaffold components of cullin-RING ubiquitin ligases (CRLs), which ubiquitinate proteins and target them for degradation by the 26S proteasome. We demonstrate that Cif directly inhibits the ubiquitin ligase activity of these CRLs and consequently the targeting of p21 and p27 for ubiquitin-dependent degradation. Targeting at NEDD8 represents a novel strategy for modulation of host cell functions by bacterial pathogens. By inhibiting the most prominent class of ubiquitin-ligases, Cif controls the stability of a cohort of key regulators and impinge on not only cell cycle progression but also on many cellular and biological processes such as immunity, development, transcription, and cell signaling.
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影响因子：
5.6
作者：
Hsu, Yun;Jubelin, Gregory;Taieb, Frederic;Nougayrede, Jean-Philippe;Oswald, Eric;Stebbins, C. Erec
通讯作者：
Stebbins, C. Erec
影响因子：
64.5
作者：
Duda, David M.;Borg, Laura A.;Scott, Daniel C.;Hunt, Harold W.;Hammel, Michal;Schulman, Brenda A.
通讯作者：
Schulman, Brenda A.
影响因子：
3.7
作者：
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通讯作者：
Banfield MJ
影响因子：
6.7
作者：
Angot, Aurelie;Vergunst, Annette;Genin, Stephane;Peeters, Nemo
通讯作者：
Peeters, Nemo
影响因子：
3.6
作者：
Marchès, O;Ledger, TN;Oswald, E
通讯作者：
Oswald, E