Kukolj G, Jones K S, Skalka A M
Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111, USA.
J Virol. 1997 Jan;71(1):843-7. doi: 10.1128/JVI.71.1.843-847.1997.
The composition and subcellular trafficking of subviral preintegration complexes are reported to vary among the different retroviruses. The process by which the avian sarcoma virus (ASV) preintegration complex gains access to target chromatin remains unknown. Here we report that ASV integrase (IN) expressed as a fusion to beta-galactosidase accumulates in the nuclei of transfected COS-1 cells. In contrast, human immunodeficiency type 1 (HIV-1) IN-beta-galactosidase fusions expressed similarly are predominantly cytoplasmic. To identify the region of ASV IN that specifies nuclear localization, various subdomains of the protein were expressed as beta-galactosidase fusions and their subcellular locations were assessed cytochemically and by indirect immunofluorescence. These analyses showed that the ASV IN protein possesses a functional nuclear localization signal that spans amino acids 206 to 235 and displays limited homology with known nuclear transport signals.
据报道，不同逆转录病毒的亚病毒整合前复合物的组成和亚细胞运输存在差异。禽肉瘤病毒（ASV）整合前复合物进入靶染色质的过程仍不清楚。在此，我们报道，与β-半乳糖苷酶融合表达的ASV整合酶（IN）在转染的COS-1细胞核中积累。相比之下，以类似方式表达的人类免疫缺陷病毒1型（HIV-1）IN-β-半乳糖苷酶融合蛋白主要位于细胞质中。为了确定ASV IN中指定核定位的区域，该蛋白的各个亚结构域作为β-半乳糖苷酶融合蛋白表达，并通过细胞化学和间接免疫荧光评估其亚细胞定位。这些分析表明，ASV IN蛋白具有一个功能性核定位信号，该信号跨越氨基酸206至235，与已知的核运输信号显示出有限的同源性。
