Whole genome analysis of codon usage in Echinococcus

MALDONADO L; STEGMAYER G; MILONE DH; OLIVEIRA G; ROSENZVIT M C; KAMENETZKY L

MOLECULAR AND BIOCHEMICAL PARASITOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2018

0166-6851

The species of the genus Echinococcus are parasitic platyhelminths that cause echinococcosis and exert a globalburden on public and animal health. Here we performed codon usage bias and comparative genomic analysesusing whole genome and expression data of three Echinococcus species. The study of 4,710,883 codons, twoorders of magnitude more than in previous research works, showed that the codon usage in Echinococcus genes isbiased towards the pyrimidines T and C ending codons, with an average effective number of codons equal to 57revealing a low codon usage bias. The gene annotations and the expression profile of 7613 genes allowed toaccurately determine 27 optimal codons for the Echinococcus species, most of them ending in G/C.Approximately the 30% of Echinococcus genes analysed exhibits higher codon usage bias as well as a higherexpression profile. Neutrality-plots demonstrated that the selection pressure is the main evolutionary forceshaping the codon usage with a contribution of 80%. Comparative genome analyses among several tapewormspecies revealed that codon usage patterns are a conserved trait in cestodes parasites. Since cestodes parasitestake advantage of the host protein synthesis pathways, this study could provide valuable information associatedwith the parasite-host relationship that would be useful to determine which host?s factors are relevant forshaping the codon usage.