黄病毒科病毒核衣壳蛋白的核仁定位在病毒颗粒包装与病毒复制中发挥重要作用。为鉴定黄病毒科的猪瘟病毒Core蛋白核仁定位序列，本研究构建了将Core蛋白、截短突变体和氨基酸位点突变体分别与增强型绿色荧光蛋白(enhanced green fluorescent protein, EGFP )融合的真核表达质粒，转染至PK15细胞后进行表达和定位分析，结果显示 Core蛋白核仁定位序列为PESRKKL，其关键氨基酸为R76K77，对理解猪瘟病毒Core蛋白结构与功能和为后续研究Core蛋白在病毒复制及颗粒包装中的作用有重要意义。

The core protein of classical swine fever virus (CSFV) is a nucleocapsid protein localized in the inner part of virion. The nucleolus localization of nucleocapsid protein of virus in family Flaviviridae plays an important role in virion packaging and virus replication. In this study, recombinant eukaryotic plasmids expressing CSFV Core protein, its truncated and amino acids mutants fused with EGFP were constructed, respectively. Subcellular localization of core protein and its mutants in the transfected PK15 cells were observed under confocal microscopy. We successfully identified the nucleolus localization sequence PESRKKL and its critical amino acids R76K77 in Core protein. Our work will further our understanding of the structure and function of CSFV Core protein and its roles in virion packaging and virus replication.