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根据对ＴＭＶ高效复制和基因表达的顺式作用元件的分析，在体外重组包装了２个缺失型ＴＭＶ粒子：ＴＭＶＲＰ和ＴＭＶＣＰ。前者缺失了ＴＭＶ外壳蛋白ＣＰ基因的３′端及后序区域，后者缺失了大部分复制酶基因。把两者分别或共同电击感染烟草原生质体：１．用ＣＰ抗体进行免疫印渍检测，单独感染的原生质体内的ＣＰ在１６小时内无增加，而在共同感染的原生质体内，ＣＰ在感染２小时后就开始明显增加。２．用ＲＴ一两次ＰＣＲ法专一地检测新生负链ＲＮＡ的合成情况，在单独感染的原生质体内没有检测到，但在混合感染的原生质体内在感染１小时后就检测到ＣＰ基因特异的负链ＲＮＡ的形成，并用Ｓｏｕｔｈｅｒｎ杂交得到进一步验证。这些结果表明，复制酶缺失型ＴＭＶＣＰ内的ＣＰ基因不能表达，但可以在ＴＭＶＲＰ存在时，通过其所表达的复制酶互补作用得到复制从而有效表达．
Based on the analysis of cis-acting elements for efficient replication and gene expression of TMV, two missing TMV particles, TMVRP and TMVCP, were recombinantly packaged in vitro. The former lacks the 3 ’end of the TMV coat protein CP gene and the subsequent region, which lacks most of the replicase gene. The two were separately or jointly electric shock infected tobacco protoplasts: 1. Immunofluorescence assay with CP antibody showed no increase in CP within the infected protoplasts alone within 16 hours, whereas in co-infected protoplasts, CP began to increase significantly after 2 hours of infection. 2. The RT-PCR method was used to detect the synthesis of new negative-negative RNAs and was not detected in the isolated infected protoplasts. However, CP gene-specific negative chains were detected within 1 hour after infection in mixed infected protoplasts RNA formation and further verification by Southern hybridization. These results indicate that the CP gene in replicative enzyme-deficient TMVCP can not be expressed, but can be efficiently replicated in the presence of TMVRP by the replicase interaction it expresses.