The sand fly Lutzomyia columbiana is considered a suspected vector of Leishmania mexicana and Leishmania braziliensis in Colombia. Lu. columbiana belongs to the Lutzomyia verrucarum species group, which included some sibling species. This has motivated the search for molecular markers to distinguish these taxa. In this paper, we described for the first time the putative secondary structure of the mitochondrial serine transfer RNA that recognizes the codon UCN of Lu. columbiana (tRNA Ser). DNA was extracted, amplified and sequenced from six individuals collected in human biting activity. The secondary structure of the tRNA Ser was inferred using the program tRNAscan-SE 1.21. The tRNA Ser gene length was 67 pair of bases (pb), and a single haplotype was detected among the six specimens sequenced. In the inferred secondary structure of the tRNA Ser of Lu. columbiana, the acceptor arm consisted of 7 bp, the dihydrouridine (DHU) arm of 3 pb, the anticodon arm of 5 pb, and the ribothymidine-pseudouridine-cytosine (TøC) arm of 5 pb. Similarity, the estimated size of the loops was 5 nucleotides in the DHU, 7 in the anticodon, 4 in the variable, and 7 in the TøC. Lu. columbiana differs from other Lutzomyia and Phlebotomus species sequenced to date by the presence of guanine in the nucleotide position 64, which induce a non-canonical base pair conformation type uracil-guanine in the acceptor arm. More studies are necessary to confirm the usefulness of the tRNA Ser as a suitable molecular tool for sand fly species identification.
Colombia; genetics; leishmaniasis; molecular taxonomy; sand fly