Link to home

Potato mop-top virus RNA Can Move Long Distance in the Absence of Coat Protein: Evidence from Resistant, Transgenic Plants

January 2000 , Volume 13 , Number  1
Pages  125 - 128

Kara D. McGeachy and Hugh Barker

Scottish Crop Research Institute, Invergowrie, Dundee, DD2 5DA, U.K.

Go to article:
Accepted 6 October 1999.

Transgenic expression of a translatable version of the Potato mop-top virus (PMTV) coat protein (CP) gene (encoded by RNA 3) in Nicotiana benthamiana prevented production of symptoms and infective virus particles. RNAs 1 and 2 accumulated in inoculated and systemic leaves but, apart from small amounts of CP transgene RNA transcript, no genomic-length RNA 3 was found. Crude leaf extracts from inoculated plants were not infective. However, when RNA extracts from such transgenic plants were inoculated to nontransgenic N. benthamiana and N. clevelandii, RNA 1 and RNA 2 replicated in systemic leaves of both species in the absence of RNA 3 and virus particles, but symptoms did not develop. We suggest that the triple-gene block proteins of PMTV (encoded by RNA 2) represent a class of long-distance RNA movement factors.

© 2000 The American Phytopathological Society