Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.
EMBO J. 2010 Nov 17;29(22):3879-90. doi: 10.1038/emboj.2010.250. Epub 2010 Oct 5.
Influenza A virus RNA replication requires an intricate regulatory network involving viral and cellular proteins. In this study, we examined the roles of cellular ubiquitinating/deubiquitinating enzymes (DUBs). We observed that downregulation of a cellular deubiquitinating enzyme USP11 resulted in enhanced virus production, suggesting that USP11 could inhibit influenza virus replication. Conversely, overexpression of USP11 specifically inhibited viral genomic RNA replication, and this inhibition required the deubiquitinase activity. Furthermore, we showed that USP11 interacted with PB2, PA, and NP of viral RNA replication complex, and that NP is a monoubiquitinated protein and can be deubiquitinated by USP11 in vivo. Finally, we identified K184 as the ubiquitination site on NP and this residue is crucial for virus RNA replication. We propose that ubiquitination/deubiquitination of NP can be manipulated for antiviral therapeutic purposes.
甲型流感病毒 RNA 复制需要一个涉及病毒和细胞蛋白的复杂调控网络。在这项研究中,我们研究了细胞泛素化/去泛素化酶(DUBs)的作用。我们发现,下调一种细胞去泛素化酶 USP11 会导致病毒产量增加,表明 USP11 可能抑制流感病毒复制。相反,USP11 的过表达特异性抑制病毒基因组 RNA 复制,这种抑制需要去泛素酶活性。此外,我们表明 USP11 与病毒 RNA 复制复合物的 PB2、PA 和 NP 相互作用,并且 NP 是一个单泛素化蛋白,可在体内被 USP11 去泛素化。最后,我们确定 NP 上的 K184 是泛素化位点,该残基对病毒 RNA 复制至关重要。我们提出可以操纵 NP 的泛素化/去泛素化来进行抗病毒治疗。