Two virus-encoded RNA silencing suppressors, P14 of Beet necrotic yellow vein virus and S6 of Rice black streak dwarf virus

摘要

Functional analysis for gene silencing suppressor of P14 gene of Beet necrotic yellow vein virus and S6 gene of Rice black streak dwarf virus was carried out by agro- infiltration with recombinant vectors of Potato virus X. The pheriotype observation of green fluorescent protein (GFP) expression and Northern blot showed that the gene silencing of gfp transgenic Nicotiana benthamiana induced by homologous sequence was strongly suppressed by the unmix -tiire infiltration of either the P14 or the S6. In the suppressed plants, the gfp mRNA accumulation was higher than that in the non-suppressed controls and the symptoms caused by PVX infection became more severe, especially the gfp DNA metliylation of plant genome was significantly inhabited when co-infiltrated with RBSBV 36 gene. These results suggested that these two virus genes were potentially to encode for proteins as RNA silencing suppressors.