Isolation of α-tubulin genes from the human malaria parasite, Plasmodium falciparum: Sequence analysis of α-tubulin

As a step towards identifying exploitable differences between host and parasite at the molecular level, we have isolated and sequenced genomic clones encompassing and entire α-tubulin gene (designated α-tubulin I) from the human malaria parasite, Plasmodium falciparum. The gene, which contains two introns, encodes a product with a predicted length of 453 amino acid residues (50.3 kD). The protein sequence shows a high degree of homology to other α-tubulins, particularly that of the coccidian parasite, Toxoplasma gondii (94%), whose gene carries introns in identical positions. Only one copy of the α-tubulin I gene itself was found, although a second gene designated α-II was also identified which is closely related but which differs at both the nucleotide and amino acid sequence levels. The α-I and β-tubulin genes were found to reside on different chromosomes.