Erratum

Abstract

Volume 21, Number 1, January 2000, pages 1–8, Sonoda and NishiguchiIncorrect text was added to the Summary of the above paper. The correct Summary is printed below.The publisher apologises for any confusion caused.SummaryUsing the grafting procedure, we examined the transmission of post‐transcriptional gene silencing (PTGS) in Nicotiana benthamiana which had been transformed with the coat protein gene, including the 3′ non‐translated region of the sweet potato feathery mottle potyvirus. Transmission of PTGS from silenced lines to non‐silenced ones was bidirectional, but occurred efficiently from root stocks to scions. The level of transgene methylation in non‐silenced scions grafted onto silenced root stocks was not increased. When grafted scions which had become silenced were removed from silenced root stocks and regrafted onto non‐silenced or vector‐transformed root stocks, PTGS was maintained. However, their progeny did not show PTGS. Previously we reported that our transgenic lines had different target specificities of PTGS for RNA degradation: one line recognized only the 3′ part of the transgene mRNA while others involved the whole transgene mRNA (Sonoda et al. 1999, Phytopathology, 89, 385–391). Using these lines, we showed that target specificity of PTGS induced in non‐silenced scions after grafting was determined by that in silenced root stocks. However, unexpectedly, target specificity of PTGS in silenced scions was not changed by grafting onto silenced root stocks showing different target specificity, indicating that the second PTGS from silenced root stocks was not superimposed to silenced scions.