Identification and functional characterization of Bet protein as a negative regulator of BFV3026 replication
Identification and functional characterization of Bet protein as a negative regulator of BFV3026 replication
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Bet 蛋白作为 BFV3026 复制负调节因子的鉴定和功能表征
DOI：
10.1007/s11262-014-1052-1
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发表时间：
2014-06-01
期刊：
影响因子：
1.6
通讯作者：
Qiao, Wentao
中科院分区：
文献类型：
--
作者：
Bing, Tiejun;Wu, Kai;Qiao, Wentao
泡沫病毒（FV）在宿主体内建立持续感染，但不会引起明显的疾病。除了反式激活蛋白Tas之外，在原型泡沫病毒、马泡沫病毒和猫泡沫病毒中还报道了另一种辅助蛋白Bet。在这里，我们通过与其他已知bet基因的基因定位、组成和剪接特征进行比较，在牛泡沫病毒株3026（BFV3026）的cDNA文库中的克隆C74中发现了假定的bbet基因。随后，通过蛋白质印迹和免疫荧光分析在 BFV3026 感染的细胞中检测到 BBet 蛋白。对 BBet 突变感染性克隆 (pBS-BFVdelBBet) 的分析表明，BBet 可以抑制 BFV3026 复制。与这一结果一致，Cf2Th 细胞中 BBe 的过度表达使 BFV 复制减少了大约三倍。此外，与对照细胞相比，稳定表达 BBet 的 pBS-BFV 转染和 BFV3026 感染的 Cf2Th 细胞中的病毒复制水平类似地降低了约三倍。传代三代后，BFV3026 在表达 BBet 的细胞中复制得更慢。这项研究表明 BBet 是 BFV 复制的负调节因子，并为未来研究该蛋白在病毒生命周期中的功能提供了资源。
Foamy virus (FV) establishes persistent infection in the host without causing apparent disease. Besides the transactivator Tas protein, another auxiliary protein-Bet-has been reported in prototype foamy virus, equine foamy virus, and feline foamy virus. Here, we found the putative bbet gene in clone C74 from a cDNA library of bovine foamy virus strain 3026 (BFV3026) by comparison of gene localization, composition, and splicing features with other known bet genes. Subsequently, BBet protein was detected in BFV3026-infected cells by Western blot and immunofluorescence analyses. Analysis of the BBet mutant infectious clone (pBS-BFVdelBBet) revealed that BBet could inhibit BFV3026 replication. Consistent with this result, overexpression of BBet in Cf2Th cells reduced BFV replication by approximately threefold. Furthermore, virus replication levels similarly were reduced by approximately threefold in pBS-BFV-transfected and BFV3026-infected Cf2Th cells stably expressing BBet compared with control cells. After three passages, BFV3026 replicated more slowly in BBet-expressing cells. This study implicates BBet as a negative regulator of BFV replication and provides a resource for future studies on the function of this protein in the virus lifecycle.