Structural analysis of a necrogenic strain of cucumber mosaic cucumovirus satellite RNA in planta.
Structural analysis of a necrogenic strain of cucumber mosaic cucumovirus satellite RNA in planta.
复制标题
DOI：
10.1006/viro.1997.8731
复制
发表时间：
1997-09
期刊：
影响因子：
3.7
通讯作者：
Gerardo Rodriguez-Alvarado;M. Roossinck
中科院分区：
文献类型：
--
作者：
Gerardo Rodriguez-Alvarado;M. Roossinck
植物病毒RNA分子的结构研究一直基于体外化学和酶促修饰。这种方法，沿着突变分析，已被证明在预测一些植物病毒如烟草花叶病毒和雀麦花叶溴病毒的结构模型方面很有价值。然而，在植物条件可能是显着不同的那些在体外发现。在这项研究中，我们分析了黄瓜花叶病毒卫星RNA（sat RNA）株D4在体内的结构，并将其与体外和纯化的病毒粒子中发现的结构进行了比较。根据一种确定完整植物组织内18 S rRNA结构的方法，在体内、体外和病毒体中发现了D4-sat RNA分子的腺苷和胞嘧啶修饰的不同模式。这种化学探测程序识别位于RNA分子未配对区域的腺苷和胞嘧啶残基。甲基化数据、星星RNA折叠程序中的遗传算法和78个卫星CMV RNA序列的序列比对比较用于鉴定位于RNA分子5'和3'末端的几个螺旋区域。从以前的卫星RNA菌株诱导番茄植株坏死和那些菌株不诱导坏死之间的突变和序列比较研究的数据，使我们能够确定一个螺旋和两个四环区域相关的坏死综合征。
Structural studies of plant viral RNA molecules have been based on in vitro chemical and enzymatic modification. That approach, along with mutational analysis, has proven valuable in predicting structural models for some plant viruses such as tobacco mosaic tobamovirus and brome mosaic bromovirus. However, in planta conditions may be dramatically different from those found in vitro. In this study we analyzed the structure of cucumber mosaic cucumovirus satellite RNA (sat RNA) strain D4 in vivo and compared it to the structures found in vitro and in purified virions. Following a methodology developed to determine the structure of 18S rRNA within intact plant tissues, different patterns of adenosine and cytosine modification were found for D4-sat RNA molecules in vivo, in vitro, and in virions. This chemical probing procedure identifies adenosine and cytosine residues located in unpaired regions of the RNA molecules. Methylation data, a genetic algorithm in the STAR RNA folding program, and sequence alignment comparisons of 78 satellite CMV RNA sequences were used to identify several helical regions located at the 5' and 3' ends of the RNA molecule. Data from previous mutational and sequence comparison studies between satellite RNA strains inducing necrosis in tomato plants and those strains not inducing necrosis allowed us to identify one helix and two tetraloop regions correlating with the necrogenicity syndrome.