Filogenômica e arquitetura de genomas plastidiais em Chrysobalanaceae (Malpighiales)

Abstract

Chrysobalanaceae is one of the families of the order Malpighiales whose taxonomy has challenged science for over two centuries. The family comprises 27 genera and approximately 550 species with a predominantly tropical distribution, spanning the Americas, Africa, and Southeast Asia. In the last 20 years, advances in molecular studies of the family have made it possible to resolve problems in the group's taxonomy, including the confirmation of its monophyly and major changes in generic delimitation. Studies involving complete plastid genomes aimed to resolve the phylogenetic relationships among the genera of the family, but other questions remain unexplored, such as the characterization of structural aspects of the genomes. The present study explored the comparison of plastid genome architecture of Chrysobalanaceae, investigating the presence of gene duplications and gene losses, in addition to variations in gene size and intron regions, with the aim of characterizing the plastomes of the species and analyzing the molecular events in a phylogenetic context. Genomic comparisons revealed regions of high variability, such as the ycf1b gene, which may function as a barcode for species delimitation in Chrysobalanaceae. Our results show that the sequenced plastomes of Chrysobalanaceae species are highly conserved in terms of gene synteny, even in clades with complex biogeographic history. However, the comparison among different aspects of the genome structure across subclades showed that such analyses could provide support for integrative taxonomic studies and for a better understanding of the evolutionary processes in Chrysobalanaceae.