Transgenic plants expressing the TGB1 protein of peanut clump virus complement movement of TGB1-defective peanut clump virus but not of TGB1-defective beet necrotic yellow vein virus

The triple gene block (TGB) of peanut clump virus (PCV) is indispensable fo r cell-to-cell movement, To determine if the TGB gene arrangement is necess ary for viral multiplication, we introduced the p51 gene corresponding to t he first: PCV TGB protein into Nicotiana benthamiana plants; high-level exp ression of P51 was obtained in regenerated transformed plants. Two lines of the R5 generation of transgenic plants were used for complementation exper iments. To this end deficient PCV RNA 2 transcripts (p51 deletion mutant, R NA 2 Delta 51) which could not multiply in the whole plant were co-inoculat ed with wild-type PCV RNA 1 transcripts into P51-transgenic plants, Viral m ultiplication was observed in 19%-67% of the transgenic plants, depending u pon the line, However, no trans-complementation was observed when P51-trans genic planes were inoculated wish beet necrotic yellow vein virus defective in the corresponding TGB1 protein, the: P42 protein.