宿主DNA连接酶在肝炎病毒共价闭合环状DNA形成中的作用

StephenW

The role of host DNA ligases in hepadnavirus covalently closed circular DNA formation.Long Q1,2, Yan R1, Hu J2, Cai D1, Mitra B1, Kim ES1, Marchetti A1, Zhang H1, Wang S1, Liu Y1, Huang A2, Guo H1.
Author information
1Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America.2Institute for Viral Hepatitis, Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, the Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.

AbstractHepadnavirus covalently closed circular (ccc) DNA is the bona fide viral transcription template, which plays a pivotal role in viral infection and persistence. Upon infection, the non-replicative cccDNA is converted from the incoming and de novo synthesized viral genomic relaxed circular (rc) DNA, presumably through employment of the host cell's DNA repair mechanisms in the nucleus. The conversion of rcDNA into cccDNA requires preparation of the extremities at the nick/gap regions of rcDNA for strand ligation. After screening 107 cellular DNA repair genes, we herein report that the cellular DNA ligase (LIG) 1 and 3 play a critical role in cccDNA formation. Ligase inhibitors or functional knock down/out of LIG1/3 significantly reduced cccDNA production in an in vitro cccDNA formation assay, and in cccDNA-producing cells without direct effect on viral core DNA replication. In addition, transcomplementation of LIG1/3 in the corresponding knock-out or knock-down cells was able to restore cccDNA formation. Furthermore, LIG4, a component in non-homologous end joining DNA repair apparatus, was found to be responsible for cccDNA formation from the viral double stranded linear (dsl) DNA, but not rcDNA. In conclusion, we demonstrate that hepadnaviruses utilize the whole spectrum of host DNA ligases for cccDNA formation, which sheds light on a coherent molecular pathway of cccDNA biosynthesis, as well as the development of novel antiviral strategies for treatment of hepatitis B.


PMID:29287110DOI:10.1371/journal.ppat.1006784

StephenW

宿主DNA连接酶在肝炎病毒共价闭合环状DNA形成中的作用。
Long Q1,2，Yan R1，Hu J2，Cai D1，Mitra B1，Kim ES1，Marchetti A1，Zhang H1，Wang S1，Liu Y1，Huang A2，Guo H1。
作者信息

1
    美利坚合众国印第安纳州印第安纳大学医学院微生物与免疫学系。
2
    重庆医科大学附属第二医院感染性疾病分子生物学教育部重点实验室病毒性肝炎研究所。

抽象

嗜肝DNA病毒共价闭合环（ccc）DNA是真正的病毒转录模板，在病毒感染和持续性中起关键作用。在感染后，非复制性cccDNA从进入和从头合成的病毒基因组松弛环状（rc）DNA转变，推测可能是通过在细胞核中使用宿主细胞的DNA修复机制。将rcDNA转化为cccDNA需要在rcDNA的缺口/缺口区域制备末端以用于链连接。在筛选了107个细胞DNA修复基因之后，我们在此报道细胞DNA连接酶（LIG）1和3在cccDNA形成中起关键作用。 Lig1 / 3的连接酶抑制剂或功能性敲除/敲除显着减少体外cccDNA形成测定中的cccDNA产生，以及在对病毒核心DNA复制没有直接影响的cccDNA产生性细胞中显着减少cccDNA产生。此外，LIG1 / 3在相应的敲除或敲除细胞中的互补作用能够恢复cccDNA的形成。此外，发现LIG4（非同源末端连接DNA修复装置中的组分）负责从病毒双链线性（dsl）DNA形成cccDNA，而不是rcDNA。总之，我们证明嗜肝DNA病毒利用宿主DNA连接酶的全部范围进行cccDNA形成，这揭示了cccDNA生物合成的连贯分子途径以及开发用于治疗乙型肝炎的新型抗病毒策略。

结论：
    29287110
DOI：
    10.1371 / journal.ppat.1006784