Qian Guanhua, Hu Bin, Zhou Danlin, Xuan Yanyan, Bai Lu, Duan Changzhu
1 Department of Cell Biology and Medical Genetics, Chongqing Medical University , Chongqing, China .
DNA Cell Biol. 2015 May;34(5):327-32. doi: 10.1089/dna.2014.2714. Epub 2015 Feb 9.
Np95/ICBP90-like RING finger protein (NIRF), a novel E3 ubiquitin ligase, has been shown to interact with HBc and promote its degradation. This study investigated the effects of NIRF on replication of hepatitis B virus (HBV) and the mechanisms. We have shown that NIRF inhibits replication of HBV DNA and secretion of HBsAg and HBeAg in HepG2 cells transfected with pAAV-HBV1.3. NIRF also inhibits the replication and secretion of HBV in a mouse model that expressed HBV. NIRF reduces acetylation of HBV cccDNA-bound H3 histones. These results showed that NIRF is involved in the HBV replication cycle not only through direct interaction with HBc but also reduces acetylation of HBV cccDNA-bound H3 histones.
Np95/ICBP90样环指蛋白（NIRF）是一种新型E3泛素连接酶，已被证明可与乙肝核心蛋白（HBc）相互作用并促进其降解。本研究调查了NIRF对乙型肝炎病毒（HBV）复制的影响及其机制。我们发现，在转染了pAAV-HBV1.3的HepG2细胞中，NIRF可抑制HBV DNA的复制以及乙肝表面抗原（HBsAg）和乙肝e抗原（HBeAg）的分泌。NIRF在表达HBV的小鼠模型中也可抑制HBV的复制和分泌。NIRF可降低与HBV共价闭合环状DNA（cccDNA）结合的H3组蛋白的乙酰化水平。这些结果表明，NIRF不仅通过与HBc直接相互作用参与HBV复制周期，还可降低与HBV cccDNA结合的H3组蛋白的乙酰化水平。
