Vaccinia virus virulence factor N1 can be ubiquitylated on multiple lysine residues.
Vaccinia virus virulence factor N1 can be ubiquitylated on multiple lysine residues.
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DOI：
10.1099/vir.0.065664-0
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发表时间：
2014-09
期刊：
影响因子：
--
通讯作者：
Smith GL
中科院分区：
文献类型：
--
作者：
Maluquer de Motes C;Schiffner T;Sumner RP;Smith GL
泛素化是一种共价的翻译后修饰，调节蛋白质的稳定性，参与许多生物学功能。蛋白质可以用单一泛素链或泛素链修饰。病毒已经进化出多种机制来扰乱细胞泛素系统，并为了自己的利益而操纵它。在这里，我们报告了牛痘病毒(VACV)蛋白N1的泛素化。N1是核因子NF-κB和细胞凋亡的抑制因子，与毒力有关，具有Bcl2样折叠，在正痘病毒中高度保守。N1和泛素之间的相互作用发生在VACV感染过程中的内源性蛋白水平上，以及N1的异位表达之后。生化分析表明，N1是共价泛素化的，并且鉴定出泛素化和非泛素化的N1单体的杂二聚体，这表明泛素化并不抑制N1的二聚化。对其他VACV Bcl2蛋白，如C6或B14的研究表明，尽管这些蛋白也与泛素相互作用，但这些作用是非共价的。最后，N1的突变表明泛素化在多个受体位点上以传统的赖氨酸依赖的方式发生，因为只有一个没有赖氨酸残基的N1等位基因保持不变。综上所述，我们描述了VACV蛋白N1的一个以前未被表征的修饰，它为这种毒力因子的生物学提供了一个新的复杂性层，并提供了痘病毒和宿主泛素系统之间复杂相互作用的另一个例子。
Ubiquitylation is a covalent post-translational modification that regulates protein stability and is involved in many biological functions. Proteins may be modified with mono-ubiquitin or ubiquitin chains. Viruses have evolved multiple mechanisms to perturb the cell ubiquitin system and manipulate it to their own benefit. Here, we report ubiquitylation of vaccinia virus (VACV) protein N1. N1 is an inhibitor of the nuclear factor NF-κB and apoptosis that contributes to virulence, has a Bcl-2-like fold, and is highly conserved amongst orthopoxviruses. The interaction between N1 and ubiquitin occurs at endogenous protein levels during VACV infection and following ectopic expression of N1. Biochemical analysis demonstrated that N1 is covalently ubiquitylated, and heterodimers of ubiquitylated and non-ubiquitylated N1 monomers were identified, suggesting that ubiquitylation does not inhibit N1 dimerization. Studies with other VACV Bcl-2 proteins, such as C6 or B14, revealed that although these proteins also interact with ubiquitin, these interactions are non-covalent. Finally, mutagenesis of N1 showed that ubiquitylation occurs in a conventional lysine-dependent manner at multiple acceptor sites because only an N1 allele devoid of lysine residues remained unmodified. Taken together, we described a previously uncharacterized modification of the VACV protein N1 that provided a new layer of complexity to the biology of this virulence factor, and provided another example of the intricate interplay between poxviruses and the host ubiquitin system.
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影响因子：
16
作者：
Kvansakul, Marc;van Delft, Mark F.;Colman, Peter M.
通讯作者：
Colman, Peter M.
影响因子：
5.4
作者：
Gonzalez-Santamaria, Jose;Campagna, Michela;Rivas, Carmen
通讯作者：
Rivas, Carmen
影响因子：
4.8
作者：
González JM;Esteban M
通讯作者：
Esteban M
影响因子：
6.7
作者：
Graham SC;Bahar MW;Cooray S;Chen RA;Whalen DM;Abrescia NG;Alderton D;Owens RJ;Stuart DI;Smith GL;Grimes JM
通讯作者：
Grimes JM
影响因子：
64.5
作者：
Garrus, JE;von Schwedler, UK;Sundquist, WI
通讯作者：
Sundquist, WI