Mapping of the Tobacco mosaic virus movement protein and coat protein subgenomic RNA promoters in vivo
Mapping of the Tobacco mosaic virus movement protein and coat protein subgenomic RNA promoters in vivo
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DOI：
10.1006/viro.2000.0511
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发表时间：
2000-09-15
期刊：
影响因子：
3.7
通讯作者：
Lewandowski, DJ
中科院分区：
文献类型：
--
作者：
Grdzelishvili, VZ;Chapman, SN;Lewandowski, DJ
烟草花叶病毒运动蛋白（MP）和外壳蛋白（CP）由3 '-共末端亚基因组RNA（sgRNA）表达。MP sgRNA的转录起始位点，先前定位于位置4838（Y.渡边T. Meshi和Y. Okada（1984），FEES Lett 173，247-250）和4828（K. Lehto，G. L. Grantham和W. O. Dawson（1990），Virology 174，145-157）分别对TMV OM和U1株系进行了重新检测，并定位到U1株系的4838位。通过缺失分析描绘MP和CP sgRNA启动子的序列。相对于转录起始位点，最小和完全MP sgRNA启动子活性的边界分别位于-35和+10以及-95和+40之间。最小CP sgRNA启动子定位在-69和+12之间，而完全活性启动子的边界在-157和+54之间。计算机分析预测了MP sgRNA转录起始位点上游的两个茎环结构（SL 1和SL 2）。缺失分析和定点诱变表明，SL 1二级结构，而不是其序列，是MP sgRNA启动子活性所需的，而39-nt的缺失去除大部分的SL 2区域增加MP sgRNA积累四倍。计算机预测的完全活性CP sgRNA启动子的折叠揭示了一个长茎环结构。删除分析表明，上标准杆？位于转录起始位点上游的这个茎环的一部分对于转录是必不可少的，并且茎的下部具有增强作用，（C）2000学术出版社。
The Tobacco mosaic virus movement protein (MP) and coat protein (CP) are expressed from 3'-coterminal subgenomic RNAs (sgRNAs). The transcription start site of the MP sgRNA, previously mapped to positions 4838 (Y. Watanabe, T. Meshi, and Y. Okada (1984), FEES Lett 173, 247-250) and 4828 (K. Lehto, G. L. Grantham, and W. O. Dawson (1990), Virology 174, 145-157) for the TMV OM and U1 strains, respectively, has been reexamined and mapped to position 4838 for strain U1. Sequences of the MP and CP sgRNA promoters were delineated by deletion analysis. The boundaries for minimal and full MP sgRNA promoter activity were localized between -35 and +10 and -95 and +40, respectively, relative to the transcription start site. The minimal CP sgRNA promoter was mapped between -69 and +12, whereas the boundaries of the fully active promoter were between -157 and +54. Computer analysis predicted two stem-loop structures (SL1 and SL2) upstream of the MP sgRNA transcription start site. Deletion analysis and site-directed mutagenesis suggested that SL1 secondary structure, bur not its sequence, was required for MP sgRNA promoter activity, whereas a 39-nt deletion removing most of the SL2 region increased MP sgRNA accumulation fourfold. Computer-predicted folding of the fully active CP sgRNA promoter revealed one long stem-loop structure. Deletion analysis suggested that the upper par? of this stem-loop, located upstream of the transcription start site, was essential for transcription and that the lower part of the stem had an enhancing role, (C) 2000 Academic Press.