Figure 2

Schematic summary of the new family of plasmid vectors. Plasmids are designated by the pfYC prefix, a series number (1-4) and a number (0-4) defining the resistance marker present in expression cassette A (5′PfCaM/3′PfHsp86 UTRs) or B (5′-PcDT/3′PfHRPII UTRs). The series number is defined by specific utility features included in the plasmid as follows: 1 = yeast CEN/ARS origin to enable plasmid maintenance in S. cerevisiae during yeast HR and a 2 × Rep20 element to improve plasmid segregation in P. falciparum[19]; 2 = same as in 1, but with a 2 × attP element added to enable site-specific chromosomal integration into existing attB⁺ strains [18]; 3 = 2 × attP element is present, but the yeast CEN/ARS origin and 2 × Rep20 elements have been eliminated; and 4 = the pfcen5-1.5 mini-centromere element is included to facilitate plasmid segregation and maintenance at single copy in P. falciparum[20], while the yeast origin, 2 × Rep20 and 2 × attP elements have been eliminated. P. falciparum resistance markers are designated as: 0 = none; 1 = nptII (G-418 resistance); 2 = bsd (Blasticidin S resistance); 3 = hdhfr (WR99210 resistance); and 4 = ydhodh (DSM-1 resistance). A non-resistance gene cloned into the available expression cassette is indicated by a colon followed by the gene name (e g, pfYC110:FL indicates that the nptII and firefly luciferase genes are present in expression cassettes A and B, respectively). Three HindIII sites present on the base plasmid are noted, as they are useful for topologically mapping these vectors and derivatives to screen for potential rearrangements and large insertions or deletions.