Maule A J, Thomas C M
Nucleic Acids Res. 1985 Oct 25;13(20):7359-73. doi: 10.1093/nar/13.20.7359.
Two-dimensional electrophoresis of cauliflower mosaic virus (CaMV) virion DNA and analysis of Southern blots using (+) strand-specific probes to the 5' termini of the beta (5.4 Kb) and alpha (2.6 Kb) strands, revealed the presence of molecules in addition to those predicted from the known structure of CaMV DNA. The presence of 8 Kb molecules of (+) sense after denaturation suggested that a small proportion of circular molecules have only a single discontinuity in the (+) strand. Other molecules, probably 5' coterminal with the beta strand but smaller than 5.4 Kb, indicated that a minority of the circular full length CaMV DNA contain additional gaps in the (+) strand. Consequently, molecules equivalent to the remainder of the beta strand could be identified using a single strand probe for a region towards the 3'-end of the beta strand. Computer analysis of the nucleotide sequence of CaMV DNA in the region of the proposed additional discontinuities revealed regions displaying some homology with the major (+) strand priming sites at the 5' ends of the beta and alpha strands. It is our contention that the additional (+) strand molecules of beta specificity are a consequence of minor (+) strand priming sites.
花椰菜花叶病毒（CaMV）病毒粒子DNA的二维电泳以及使用针对β（5.4 Kb）和α（2.6 Kb）链5'末端的（+）链特异性探针进行Southern印迹分析，结果显示除了从CaMV DNA已知结构预测的分子外，还存在其他分子。变性后出现的8 Kb（+）链分子表明，一小部分环状分子在（+）链中仅有一个间断。其他分子可能与β链5'端共末端，但小于5.4 Kb，这表明少数环状全长CaMV DNA在（+）链中含有额外的缺口。因此，使用针对β链3'端区域的单链探针可以鉴定出与β链其余部分等效的分子。对CaMV DNA中拟议的额外间断区域的核苷酸序列进行计算机分析，发现了与β和α链5'端主要（+）链引发位点具有一定同源性的区域。我们认为，具有β特异性的额外（+）链分子是次要（+）链引发位点的结果。
