Análise in silico de relações filogenéticas de plantas baseadas no gene ga20ox

Abstract

Online data are submitted and consulted in these remote banks. Currently there are approximately 127 million DNA sequences in the NCBI, enabling the performance of several in silico studies, including studies on systematics. The plastid genes are most commonly used in phylogenetic analyzes due to its efficacy, while nuclear genes have been little exploited in this context, leaving a vast field for preliminary studies. This study investigated the efficacy of the nuclear gene GA20ox1 in resolving phylogenetic relationships within the eudicots. Sequences of the rbcL gene were employed for comparison. All sequences were obtained directly from the GenBank. The efficacy of this gene was evaluated by determining the rate of transversions/transitions, proportion of parsimony-informative characters, retention index (RI) and consistency index (CI) and through the construction of phylogenetic trees. The rate of transversions/transitions mutations and proportion of parsimony-informative characters of the GA20ox1 gene suggest high informative capacity, although the RI and CI values were relatively low. The phylogenetic tree based on the GA20ox gene was partially congruent with the phylogenetic reconstruction based on the rbcL sequences and with the tree recognized by the APG III. The observed incongruence reflect the different evolutionary ways followed by the different groups of plants concerning this gene. The results obtained revealed enough phylogenetic signal in the GA20ox1 gene to group species at family level, being useful to resolve the phylogenetic relationships at lower taxonomic levels and increase our knowledge about the evolution of flowering plants.