Junqing Sun, Lu Kuai, Lei Zhang, Yufeng Xie, Yanfang Zhang, Yan Li, Qi Peng, Yuekun Shao, Qiuxian Yang, Wen-Xia Tian, Junhao Zhu, Jianxun Qi, Yi Shi, Tao Deng, George F Gao
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引用次数: 0
Abstract
Genome transcription and replication of influenza A virus (FluA), catalyzed by viral RNA polymerase (FluAPol), are delicately controlled across the virus life cycle. A switch from transcription to replication occurring at later stage of an infection is critical for progeny virion production and viral non-structural protein NS2 has been implicated in regulating the switch. However, the underlying regulatory mechanisms and the structure of NS2 remained elusive for years. Here, we determine the cryo-EM structure of the FluAPol-NS2 complex at ~3.0 Å resolution. Surprisingly, three domain-swapped NS2 dimers arrange three symmetrical FluPol dimers into a highly ordered barrel-like hexamer. Further structural and functional analyses demonstrate that NS2 binding not only hampers the interaction between FluAPol and the Pol II CTD because of steric conflicts, but also impairs FluAPol transcriptase activity by stalling it in the replicase conformation. Moreover, this is the first visualization of the full-length NS2 structure. Our findings uncover key molecular mechanisms of the FluA transcription-replication switch and have implications for the development of antivirals.
期刊介绍:
EMBO Reports is a scientific journal that specializes in publishing research articles in the fields of molecular biology, cell biology, and developmental biology. The journal is known for its commitment to publishing high-quality, impactful research that provides novel physiological and functional insights. These insights are expected to be supported by robust evidence, with independent lines of inquiry validating the findings.
The journal's scope includes both long and short-format papers, catering to different types of research contributions. It values studies that:
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EMBO Reports is dedicated to maintaining high standards of scientific rigor and integrity, ensuring that the research it publishes contributes meaningfully to the advancement of knowledge in the life sciences. By covering a broad spectrum of topics and encouraging the publication of both positive and negative results, the journal plays a vital role in promoting a comprehensive and balanced view of scientific inquiry.