[13] Amplification of ABC transporter gene pgpA and of other heavy metal resistance genes in Leishmania tarentolae and their study by gene transfection and gene disruption

Publisher Summary This chapter describes the amplicons that can be detected and isolated. It also explains how the function of heavy metal resistance genes in Leishmania can be studied by gene transfection and gene disruption. Resistance to oxyanions in Leishmania is a complex phenomenon. The ease of detection of gene amplification has permitted the isolation of genes involved in resistance including one encoding for the ABC transporter PgpA and for a gene collaborating with it. Several other amplified genes in L. tarentolae , resistant to oxyanions have been isolated using the methodology described in the chapter. Studies of drug resistance mechanisms in parasites are correlative with the ability to introduce genes by electroporation. By disrupting the genes by homologous recombination, the role of genes in resistance can be directly studied. With the increased understanding of resistance mechanisms in laboratory strains, the resistance mechanisms prevailing in field strains isolated from patients who are unresponsive to pentavalent antimony treatment are tested. This is beneficial for the millions of people suffering from Leishmania infections.