RNA interference cassette:
Transcription of the cassette produces a hairpin RNA (hpRNA). RNA polymerase is recruited to the Cassava vein mosaic virus promoter and then transcribes: two segments of Cassava Brown Streak Virus (CBSV) and the Ugandan Cassava Brown Streak Virus (UCBSV) coat protein (sense orientation), the Flaveria trinervia pyruvate orthophosphate dikinase intron 3 (PDK), and CBSV and UCBSV coat protein (anti-sense orientation). Transcription stops at the Agrobacterium tumefaciens nopaline synthase (nos) terminator. The produced RNA then can form a double stranded segment due to the interstrand homology between the CBSV and UCBSV coat protein segments and the flexible linker/loop, PDK. The double stranded segment of the hpRNA is sufficient to trigger an RNA interference (RNAi) response. The host cell machinery then processes the hpRNA into small interfering RNA, which is used to guide the targeted degradation of RNA molecules with sequence homology. In this case, infecting viral transcripts are degraded by the host cell.

Iron-regulated transporter cassette:
Transcription of the Arabidopsis thaliana iron-regulated transporter 1 is under control of the A. thaliana phloem protein 2-A14 promoter and terminator.

Ferritin-1 cassette:
Arabidopsis thaliana ferritin-1 is under transcriptional control of the Solanum tuberosum patatin-1 promoter and terminator.

Selectable marker cassette:
Transcription of the Escherichia coli neomycin phosphotransferase II occurs from the duplicated enhanced Cauliflower Mosaic Virus 35S promoter and terminates at the nos terminator.

Please note all genetic elements were in the anti-sense orientation.