Figure 8. MRPA locus amplification upon arsenite selection and the role of the RAD51 recombinase.

(A) The MRPA locus and the repeats allowing its amplifications are shown; DRs are A–A′, A–A″, B–B′, and C–C′ and IRs are D–D′. Primers 1–9 were used to determine the rearrangements that occurred in L. infantum WT cells (B), in RAD51 ^−/− (C), and in RAD51 add-back revertant parasites (D) all selected for arsenite resistance (up to 250 µM = 5×EC₅₀). The DNA of resistant clones was separated by pulse-field gel electrophoresis and hybridized to a MRPA probe. The rearrangement point for each amplicon was determined by PCR (Figure S7) and is indicated below for each lane. Lane 1, unselected population; lanes 2–10, independent arsenite-resistant clones.