Lv Qizhuang, Guo Kangkang, Wang Tao, Zhang Chengcheng, Zhang Yanming
College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100, China.
J Biosci. 2015 Sep;40(3):477-85. doi: 10.1007/s12038-015-9551-3.
Porcine circovirus type 2 (PCV2) is the primary infectious agent of PCV-associated disease (PCVAD) in swine. ORF4 protein is a newly identified viral protein of PCV2 and is involved in virus-induced apoptosis. However, the molecular mechanisms of ORF4 protein regulation of apoptosis remain unclear, especially given there is no information regarding any cellular partners of the ORF4 protein. Here, we have utilized the yeast two-hybrid assay and identified four host proteins (FHC, SNRPN, COX8A and Lamin C) interacting with the ORF4 protein. Specially, FHC was chosen for further characterization due to its important role in apoptosis. GST pull-down, subcellular co-location and co-immunoprecipitation assays confirmed that the PCV2 ORF4 protein indeed interacted with the heavy-chain ferritin, which is an interesting clue that will allow us to determine the role of the ORF4 protein in apoptosis.
猪圆环病毒2型（PCV2）是猪圆环病毒相关疾病（PCVAD）的主要感染因子。ORF4蛋白是PCV2新鉴定出的病毒蛋白，参与病毒诱导的细胞凋亡。然而，ORF4蛋白调控细胞凋亡的分子机制仍不清楚，特别是鉴于尚无关于ORF4蛋白任何细胞伴侣的信息。在此，我们利用酵母双杂交试验鉴定出四种与ORF4蛋白相互作用的宿主蛋白（FHC、SNRPN、COX8A和核纤层蛋白C）。特别地，由于FHC在细胞凋亡中起重要作用，因此选择对其进行进一步表征。谷胱甘肽S-转移酶（GST）沉降、亚细胞共定位和免疫共沉淀试验证实，PCV2 ORF4蛋白确实与重链铁蛋白相互作用，这是一条有趣的线索，将有助于我们确定ORF4蛋白在细胞凋亡中的作用。
