Similar Modes of Interaction Enable Trailer Hitch and EDC3 To Associate with DCP1 and Me31B in Distinct Protein Complexes
Similar Modes of Interaction Enable Trailer Hitch and EDC3 To Associate with DCP1 and Me31B in Distinct Protein Complexes
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DOI：
10.1128/mcb.00759-08
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发表时间：
2008-11-01
影响因子：
5.3
通讯作者：
Truffault, Vincent
中科院分区：
文献类型：
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作者：
Tritschler, Felix;Eulalio, Ana;Truffault, Vincent
TRAVER Hitch(Tral或LSm15)和Decaping-3增强子(EDC3或LSm16)是(L)Sm(Sm和Like-Sm)蛋白家族中保守的真核成员。它们具有相似的结构域组织，特征是N-末端的LSM结构域和中心的FDF基序；然而，在Tral中，FDF基序的两侧是富含电荷残基的区域，而在EDC3中，FDF基序后面是YjeF_N结构域。我们发现在果蝇细胞中，Tral和EDC3与去包裹激活物DCP1和死盒解旋酶Me31B特异地相互作用。然而，只有Tral与翻译抑制物CUP有关，而EDC3与解帽酶DCP2有关。与EDC3一样，Tral与DCP1相互作用，并通过LSM结构域定位于mRNA处理体(P体)。该结构域在溶液中保持单体，并采用发散的Sm折叠，如核磁共振分析所确定的那样，该折叠缺乏特征的N-末端α-螺旋。突变分析表明，Tral与DCP1和CUP相互作用并定位于P小体都需要LSM结构域的结构完整性。此外，Tral和EDC3都通过其FDF基序与Me31B的C端RecA样结构域相互作用。结合以往的研究，我们的结果表明，Tral和EDC3在结构上是相关的，并使用类似的方式与不同蛋白质复合体中的共同伙伴结合。
Trailer Hitch (Tral or LSm15) and enhancer of decapping-3 (EDC3 or LSm16) are conserved eukaryotic members of the (L) Sm (Sm and Like-Sm) protein family. They have a similar domain organization, characterized by an N-terminal LSm domain and a central FDF motif; however, in Tral, the FDF motif is flanked by regions rich in charged residues, whereas in EDC3 the FDF motif is followed by a YjeF_N domain. We show that in Drosophila cells, Tral and EDC3 specifically interact with the decapping activator DCP1 and the DEAD-box helicase Me31B. Nevertheless, only Tral associates with the translational repressor CUP, whereas EDC3 associates with the decapping enzyme DCP2. Like EDC3, Tral interacts with DCP1 and localizes to mRNA processing bodies ( P bodies) via the LSm domain. This domain remains monomeric in solution and adopts a divergent Sm fold that lacks the characteristic N-terminal alpha-helix, as determined by nuclear magnetic resonance analyses. Mutational analysis revealed that the structural integrity of the LSm domain is required for Tral both to interact with DCP1 and CUP and to localize to P-bodies. Furthermore, both Tral and EDC3 interact with the C-terminal RecA-like domain of Me31B through their FDF motifs. Together with previous studies, our results show that Tral and EDC3 are structurally related and use a similar mode to associate with common partners in distinct protein complexes.