REVERSIBLE NUCLEOLAR TRANSLOCATION OF EPSTEIN-BARR VIRUS-ENCODED EBNA-5 AND HSP70 PROTEINS AFTER EXPOSURE TO HEAT-SHOCK OR CELL-DENSITY CONGESTION
REVERSIBLE NUCLEOLAR TRANSLOCATION OF EPSTEIN-BARR VIRUS-ENCODED EBNA-5 AND HSP70 PROTEINS AFTER EXPOSURE TO HEAT-SHOCK OR CELL-DENSITY CONGESTION
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DOI：
10.1099/0022-1317-76-10-2423
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发表时间：
1995-10-01
影响因子：
3.8
通讯作者：
RINGERTZ, N
中科院分区：
文献类型：
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作者：
SZEKELY, L;JIANG, WQ;RINGERTZ, N
Epstein-Barr 病毒 (EBV) 编码的核基质相关 EBNA-5 蛋白优先定位于 EBV 永生化淋巴母细胞系的不同核斑点内。我们之前发现相同的斑点还含有视网膜母细胞瘤（Rb）蛋白。我们现在证明它们也含有 hsp70 蛋白。在细胞密度充血或热休克后，EBNA-5 和 hsp70 都会易位至核仁。恢复正常生理条件后，两种蛋白质都会重新定位到原来的位置。 EBNA-5 与核基质紧密结合。易位的 EBNA-5 也与基质结构紧密相关，如基于顺序洗脱的细胞分级分离所示。 Rb 蛋白不会易位至核仁。病毒编码的 EBNA-1、-2、-3 和 -6 以及细胞 PCNA、snRNP 和细胞周期蛋白 E 也不受影响。 EBNA-5 向核仁的易位不具有物种或细胞类型特异性，因为应激条件在不同组织来源的 EBNA-5 转染的人、小鼠和大鼠细胞中诱导相同的现象。
The Epstein-Barr virus (EBV)-encoded, nuclear matrix-associated EBNA-5 protein is preferentially localized within distinct nuclear blobs in EBV-immortalized lymphoblastoid cell lines. We have previously found that the same blobs also contain retinoblastoma (Rb) protein. We now show that they contain hsp70 protein as well. Both EBNA-5 and hsp70 translocate to the nucleolus under cell density congestion or after heat shock. Both proteins relocate to their original position upon the reestablishment of normal physiological conditions. EBNA-5 is tightly bound to the nuclear matrix. The translocated EBNA-5 is also tightly associated with matrix structures, as shown by sequential elution-based cell fractionation. The Rb protein does not translocate to the nucleolus. The virally encoded EBNA-1, -2, -3 and -6, and cellular PCNA, snRNP and cyclin E are not affected either. The translocation of EBNA-5 to the nucleolus is not species- or cell type-specific since stress conditions induced the same phenomenon in EBNA-5-transfected human, mouse and rat cells of different tissue origins.