HERPES-SIMPLEX VIRUS INHIBITS HOST-CELL SPLICING, AND REGULATORY PROTEIN ICP27 IS REQUIRED FOR THIS EFFECT
HERPES-SIMPLEX VIRUS INHIBITS HOST-CELL SPLICING, AND REGULATORY PROTEIN ICP27 IS REQUIRED FOR THIS EFFECT
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DOI：
10.1128/jvi.68.12.7790-7799.1994
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发表时间：
1994-12-01
影响因子：
5.4
通讯作者：
SANDRIGOLDIN, RM
中科院分区：
文献类型：
--
作者：
HARDY, WR;SANDRIGOLDIN, RM
虽然大多数后生动物基因及其感染的DNA病毒都含有需要RNA剪接的内含子，但单纯疱疹病毒1型(HSV-1)编码的剪接产物相对较少。我们以前的研究表明，HSV-1即刻早期蛋白ICP27降低了感染过程中剪接的靶mRNAs的水平，并在感染过程中剪接细胞的mRNAs，提示ICP27可能在损害宿主细胞剪接方面发挥作用。在这里，我们表明，在感染野生型期间，而不是感染ICP27病毒突变体27-LacZ时，前体RNA积累成含有内含子的病毒转录本。Pre-mRNA在细胞核中的积聚大于在细胞质中的积聚，这表明影响的是剪接而不是运输。此外，在野生型感染细胞的核提取液中，β-珠蛋白前mRNA底物的剪接被抑制，但在感染27-LacZ的细胞提取液中则不受抑制。野生型感染细胞提取物中的抑制活性能够降低生化互补分析中感受态提取物的剪接效率。ICP27似乎是导致这种下降的原因，因为从感染ICP27ts突变体的细胞中提取的提取物在允许的温度下孵育后，其剪接活性显著降低，以允许构象缺陷的ICP27蛋白的复性。这些结果强烈表明，HSV-1感染通过ICP27的作用抑制宿主细胞的剪接。
While the majority of metazoan genes and those of the DNA viruses which infect them contain introns which require RNA splicing, herpes simplex virus type 1 (HSV-1) encodes relatively few spliced products. We previously showed that the HSV-1 immediate early protein ICP27 decreased the levels of spliced target mRNAs in transfections and spliced cellular mRNAs during infection, suggesting that ICP27 may function in impairing host cell splicing. Here, we show that during infections with the wild type, but not in infections with an ICP27 viral mutant termed 27-LacZ, precursor RNA accumulated for a virus transcript which contained introns. Pre-mRNA accumulation in the nucleus was greater than that in the cytoplasm, indicating that splicing rather than transport was affected. Furthermore, splicing of a beta-globin pre-mRNA substrate was inhibited in nuclear extracts from wild-type-infected cells but not in extracts from cells infected with 27-LacZ. The inhibitory activity in extracts from wild-type-infected cells was able to reduce the splicing efficiency of competent extracts in biochemical complementation assays. ICP27 appeared to be responsible for this decrease, because the splicing activity of an extract from cells infected with an ICP27 ts mutant was significantly reduced after incubation of the extract at the permissive temperature to allow renaturation of the conformationally defective ICP27 protein. These results strongly suggest that HSV-1 infection inhibits host cell splicing through the action of ICP27.