IDENTIFICATION OF SPLICED BACULOVIRUS RNAS EXPRESSED LATE IN INFECTION
IDENTIFICATION OF SPLICED BACULOVIRUS RNAS EXPRESSED LATE IN INFECTION
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DOI：
10.1016/0042-6822(91)90534-i
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发表时间：
1991-12-01
期刊：
影响因子：
3.7
通讯作者：
SUMMERS, MD
中科院分区：
文献类型：
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作者：
KOVACS, GR;GUARINO, LA;SUMMERS, MD
在本研究之前，已知苜蓿银纹夜蛾核型多角体病毒（AcMNPV）仅表达一种剪接RNA（剪接的IE 1或IE 0）。我们对AcMNPV感染草地贪夜蛾细胞过程中表达的RNA进行了分析，并鉴定了一组在感染后期表达的5个额外的剪接RNA。逆转录-聚合酶链反应分析用于确认LS（晚期，剪接）RNA的鉴定。S1核酸酶和引物延伸分析用于定位LS RNA的转录起始位点。LS 1和LS 2分别起始于-138和-117位（相对于IE 0 +1转录起始位点）。LS 1和LS 2都含有一个额外的顺反子，可能编码一种小的、高碱性的多肽。LS 3（-79）、LS 4（-22）和LS 5（+51/52）RNA仅编码预测的下游IE 0 ORF。虽然几个杆状病毒晚期基因一致转录起始位点（ATAAG）被确定在这个区域内，只有LS 5开始在这些保守的基序之一。进行S1核酸酶分析以确定是否可以检测到LS RNA的未剪接前体。在感染早期，以剪接形式检测到更大比例的IE 0 RNA;然而，在感染后期，观察到显著更大量的LS RNA的未剪接前体形式。
Previous to this study, theAutographa californicamulticapsid nuclear polyhedrosis virus (AcMNPV) was known to express only one spliced RNA (spliced IE1 or IE0). We have conducted an analysis of RNA expressed during infection ofSpodoptera frugiperdacells with AcMNPV and have identified a set of five additional spliced RNAs expressed late in infection. A reverse transcription-polymerase chain reaction analysis was used to confirm the identification of the LS (late, spliced) RNAs. S1 nuclease and primer extension analyses were used to map the transcription initiation sites of LS RNAs. LS1 and LS2 initiated at positions −138 and −117, respectively (relative to the IE0+1 transcription start site). Both LS1 and LS2 contain an additional cistron potentially encoding a small, highly basic polypeptide. LS3 (−79), LS4 (−22), and LS5 (+51/52) RNAs encode only the predicted downstream IE0 ORF. Although several baculovirus late gene consensus transcription initiation sites (ATAAG) were identified within this region, only LS5 initiated at one of these conserved motifs. An S1 nuclease analysis was done to determine whether unspliced precursors of LS RNAs could be detected. Early in infection, a greater proportion of IE0 RNA was detected in the spliced form; however, during the late phase of infection a significantly greater amount of unspliced precursor forms of LS RNAs was observed.