Comparative analysis of mitochondrial genome sequences of root-knot nematodes

L. E. GARCÍA; M. V. SÁNCHEZ PUERTA

La Serena

Congreso; ONTA XLV annual meeting; 2013

Organización de nematologos de los trópicos americanos

COMPARATIVE ANALYSIS OF MITOCHONDRIAL GENOME SEQUENCES OF ROOT-KNOT NEMATODES (Análisis comparativos de secuencias del genoma mitocondrial de nematodos del nudo) Laura E. García; M. Virginia Sánchez Puerta IBAM-CONICET & Instituto de Ciencias Básicas, Universidad Nacional de Cuyo, Alte. Brown 500, Chacras de Coria, 5505 Mendoza, Argentina. Corresponding author: evangelinagarcia84@yahoo.com.ar Mitochondria are endosymbiotic bacteria in charge of oxidative phosphorylation and other essential biochemical functions within the eukaryotic cell. The animal mitochondrial genome (mtDNA) is typically non-recombining and presents regions that evolve at markedly different rates. As a consequence, rapidly-evolving regions of the mtDNA are well suited to differentiating morphologically similar species. We characterized mitochondrial genome sequences from two species of root-knot nematodes: Meloidogyne incognita (~18 kb) and M. hapla (~16 kb). Mitochondrial sequences were mined from complete genome projects in Genbank and were analyzed regarding protein-coding genes, rRNAs and tRNAs. We studied the codon usage, substitution rates and evolution of seven genes for each species; cox1, cox2, cytb, nd1, nd3, nd4 and nd5 from M. hapla, and cox1, cox2, cox3, cytb, nd1, nd3, and nd4 from M. incognita. The nucleotide composition of the partial mtDNAs was A/T-biased, with an overall A/T content of 80.3% in M. hapla and 81.8% in M. incognita. The similarity between coding regions of M. incognita and M. hapla was 72-82%. We also identified indels within coding sequences. These findings are valuable for developing new molecular markers for taxonomic purposes at the species level in the genus Meloidogyne. Presentation: oral