Phylogenetic utility of plastidic non-coding regions: a survey for the genus Ilex L.

CASCALES J.; BRACCO M.; GARBEROGLIO MJ; POGGIO L.; GOTTLIEB AM

Foz do Iguaçu

Congreso; 11th International Congress of Plant Molecular Biology (IPMB); 2015

Herein, we investigated the degree of conservation andphylogenetic utility of 32 non-coding plastid regions (18 intergenic spacers-IGS- and 14 introns) using three Ilex speciesplastomes as case-study. Sequence data were obtained through Next GenerationSequencing and from public databases. We carried-out a pre-selection step inwhich each region was analyzed independently, using a range of Ilex species with available information(that is, 3-14 species) and a ratio of variable/constant sites measured withinalignments. From these regions, we selected 11 IGS and 7 introns as promisingmarkers. We then conducted phylogenetic analyses under Maximum Likelihood,including taxa from clades euasterids-I and euasterids-II as ingroup, and taxafrom Ericales and Malvales as outgroup. The alignment of the IGS concatenatedincluded six Ilex species and spanned14363 bp; whereas the introns alignment involved three Ilex and encompassed 6713 bp. The topology derived from IGSindicates that the two South American species (I. paraguariensis and I.dumosa) share a most recentcommon ancestral maternal lineage, and that allopatric Asian species representa different lineage thoughnot very divergent. In contrast,the topology derived from the intronic regions suggests the occurrence of twolineages in South America.Altogether, our outcomes indicate that the 18 regions selected here will beinstrumental for phylogenetic and biogeographic studies in Ilex, provided that a wider sampling is achieved.