Figure 1.

(a) Genomic organization of geminiviruses. An example of a mastrevirus is provided. Top; circular version, bottom; linearized version of genome. MP; movement protein, CP; coat protein, LIR and SIR; long and short intergenic regions; (b). Geminivirus expression constructs of past and present. Schematic representations of expression vector constructs based on geminiviruses. Top; example of an earlier expression vector. Middle; vector for co-expression of two different proteins, or complex multimeric protein such as monoclonal antibodies. Bottom; foreign gene is expressed in the form of two exons, and protein expression can only take place upon intron processing. In this case, Rep is expressed from an additional construct. GOI; gene of interest, 35S; 35S CaMV promoter, T; terminator. Hatched box; Rep gene could be present in cis in this construct, or expressed in trans from another construct. (middle construct sourced from [15], bottom construct sourced from [16]).