Identification of three ABC transporter genes in Trypanosoma brucei spp.
ABC transporters are key players in the multidrug resistance of cancer cells and yeast, and they appear to be involved in the drug resistance of various pathogenic protozoa. No member of this ubiquitous protein family has yet been described in Trypanosoma brucei spp., the causative agents of African sleeping sickness and animal trypanosomiases. However, different cases of artificially induced drug resistance were shown to be linked to a reduction in net drug uptake. We used polymerase chain reaction with degenerate oligonucleotide primers corresponding to particularly conserved regions within the ATP-binding cassette to probe the genome of T. brucei spp. for the presence of ABC transporter genes. Three different sequence segments encoding ATP-binding cassettes were identified, which, upon Southern blotting, appeared to belong to distinct genes designated Tbabc1, Tbabc2, and Tbabc3. They appear to be single-copy genes in both drug-susceptible and drug-resistant stocks of T. brucei spp., expressed in bloodstream forms as well as in the procyclic life stage. Whereas Tbabc3 shows moderate homology to various known ABC transporters, Tbabc1 and Tbabc2 are highly homologous to P-glycoprotein A of Leishmania tarentolae and to the multidrug resistance protein 1 of L. donovani, respectively.
Mäser
P
P
Swiss Tropical Institute, Basel, Switzerland.
Kaminsky
R
R
D018528:ATP-Binding Cassette Transporters / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D018507:Gene Expression Regulation, Developmental; D017125:Genes, Protozoan / Q000235:genetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012194:RNA-Directed DNA Polymerase; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014346:Trypanosoma brucei brucei / Q000737:chemistry / Q000235:genetics* / Q000254:growth & development
D018528:ATP-Binding Cassette Transporters; D012194:RNA-Directed DNA Polymerase