HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (Papers in Press[PDF]) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Google Scholar Articles by Mello, A. F. S. Articles by Perry, K. L. PubMed PubMed Citation Articles by Mello, A. F. S. Articles by Perry, K. L. Agricola Articles by Mello, A. F. S. Articles by Perry, K. L.

The capsid protein of Cowpea chlorotic mottle virus is a determinant for vector transmission by a beetle

¹ Department of Plant Pathology and Plant-Microbe Biology, Cornell University;
² Department of Plant and Soil Sciences, University of Kentucky

³ E-mail: klp3{at}cornell.edu

Cowpea chlorotic mottle virus (CCMV) is a bromovirus transmitted by species of chrysomelid beetles, including the spotted cucumber beetle, Diabrotica undecimpunctata. An experimental system was set up to identify the viral determinant(s) of the beetle transmission of CCMV. Nicotiana clevelandii was selected as an experimental plant host because it supports the replication and accumulation of both CCMV and a second member of the genus Bromoviridae, Cucumber mosaic virus (CMV). Using a reverse genetic system for CMV, a complementary DNA copy of the CCMV capsid protein gene was substituted for that of the CMV capsid protein gene. The resulting 'CMV-hybrid' consisted of wild-type CMV RNA 1, RNA 2, and a chimeric CMV RNA 3 expressing the CCMV structural protein. The CMV-hybrid replicated and formed virions in N. clevelandii; in electron micrographs the hybrid virus was indistinguishable from CCMV. In beetle feeding assays, both CCMV and the CMV-hybrid were transmitted by D. undecimpunctata, while beetle transmission of CMV was not observed. Conversely, only CMV was observed to be transmitted by the aphid Myzus persicae. Surprisingly, the CMV-hybrid was transmitted more efficiently than the parental CCMV, and a virus-induced alteration in beetle feeding behavior is proposed to account for the difference. These results indicate that the CCMV capsid protein is a viral determinant for beetle vector transmission.

Received 3 September 2009; accepted 8 October 2009.