Completion sequence and cloning of the infectious cDNA of a chb isolate of cucumber green mottle mosaic virus.

Abstract

Cucumber green mottle mosaic virus (CGMMV) is an important and widespread seed-borne virus that infects Cucurbitaceous plants. It is a member of the genus Tobamovirus in the family Virgaviridae with a monopartite (+) ssRNA genome. Here we report the complete genome sequence, construction and testing of the infectious clones of a chb isolate of CGMMV. Full-length CGMMV cDNA was cloned into the vector pUC19. The linearized vector containing full-length cDNA was used as template for in vitro transcription, and the synthesized capped transcript was highly infectious in Chenopodium amaranticolor and cucumber (Cucumis sativus). Inoculated plants showed symptoms typical of CGMMV infection. The infectivity was confirmed by mechanical transmission to new plants, RT-PCR and western blot. Progeny virus derived from infectious transcripts had the same biological and biochemical properties as wild-type virus. To our knowledge, this is the first detailed report of a biologically active transcript from CGMMV.