Ingram A, Phelan A, Dunlop J, Clements J B
Institute of Virology, University of Glasgow, UK.
J Gen Virol. 1996 Aug;77 ( Pt 8):1847-51. doi: 10.1099/0022-1317-77-8-1847.
The herpes simplex virus type 1 (HSV-1) immediate early protein IE63 acts post-transcriptionally to affect RNA 3'-processing and splicing. Functional domains such as the RGG box and zinc-finger motifs potentially provide the protein with RNA binding capacity. Here, IE63 protein expressed in E. coli, purified by affinity chromatography and used in RNA binding assays, demonstrated similar binding to RNA substrates containing poly(A) sites from different temporal classes of HSV-1 genes, RNA containing splice site recognition sequences and RNA containing no recognized processing motifs. Competition binding assays showed that IE63 binding could be competed out, suggesting that IE63 binds RNA weakly. HSV-1 infection results in an increase or stabilization in vitro of protein binding to poly(A) site-containing RNAs; IE63 is required for this effect. RNA binding assays combining purified IE63 with protein from mock-infected and HSV-1 infected nuclear extracts demonstrated no effect on protein-RNA binding patterns.
单纯疱疹病毒1型（HSV-1）的立即早期蛋白IE63在转录后发挥作用，影响RNA的3'加工和剪接。诸如RGG框和锌指基序等功能域可能赋予该蛋白RNA结合能力。在这里，在大肠杆菌中表达、通过亲和层析纯化并用于RNA结合测定的IE63蛋白，显示出与含有来自HSV-1不同时间类别的基因的聚腺苷酸化位点的RNA底物、含有剪接位点识别序列的RNA以及不含有公认加工基序的RNA具有相似的结合。竞争结合测定表明IE63的结合可以被竞争掉，这表明IE63与RNA的结合较弱。HSV-1感染导致体外与含有聚腺苷酸化位点的RNA的蛋白结合增加或稳定；这种效应需要IE63。将纯化的IE63与来自 mock感染和HSV-1感染的核提取物的蛋白进行结合的RNA结合测定表明，对蛋白-RNA结合模式没有影响。
