Yuan Xiaoling, Shan Yajun, Yao Zhenyu, Li Jianyong, Zhao Zhenhu, Chen Jiapei, Cong Yuwen
Department of Pathophysiology, Beijing Institute of Radiation Medicine, Beijing 100850, China.
Mol Cells. 2006 Apr 30;21(2):186-91.
Severe acute respiratory syndrome-associated coronavirus (SARS-CoV), a distant member of the Group 2 coronaviruses, has recently been identified as the etiological agent of severe acute respiratory syndrome (SARS). The genome of SARS-CoV contains four structural genes that are homologous to genes found in other coronaviruses, as well as six subgroup-specific open reading frames (ORFs). ORF3 encodes a predicted 154-amino-acid protein that lacks similarity to any known protein, and is designated 3b in this article. We reported previously that SARS-CoV 3b is predominantly localized in the nucleolus, and induces G0/G1 arrest and apoptosis in transfected cells. In this study, we show that SARS-CoV 3b fused with EGFP at its N- or C- terminus co-localized with a mitochondria-specific marker in some transfected cells. Mutation analysis of SARS-CoV 3b revealed that the domain spanning amino acids 80 to 138 was essential for its mitochondria localization. These results provide new directions for studies of the role of SARS-CoV 3b protein in SARS pathogenesis.
严重急性呼吸综合征相关冠状病毒（SARS-CoV）是第2组冠状病毒的远亲成员，最近被确定为严重急性呼吸综合征（SARS）的病原体。SARS-CoV的基因组包含四个与其他冠状病毒中发现的基因同源的结构基因，以及六个亚组特异性开放阅读框（ORF）。ORF3编码一种预测的154个氨基酸的蛋白质，与任何已知蛋白质均无相似性，本文将其命名为3b。我们先前报道过，SARS-CoV 3b主要定位于核仁，并在转染细胞中诱导G0/G1期阻滞和细胞凋亡。在本研究中，我们发现SARS-CoV 3b在其N端或C端与EGFP融合后，在一些转染细胞中与线粒体特异性标记物共定位。对SARS-CoV 3b的突变分析表明，跨越氨基酸80至138的结构域对其线粒体定位至关重要。这些结果为研究SARS-CoV 3b蛋白在SARS发病机制中的作用提供了新的方向。
