COMPLETE GENOME OF ACROCOMIA INTUMESCENS AND A. TOTAI CHLOROPLASTS, STRUCTURAL COMPARISON AND PATTERNS OF EVOLUTIONARY DYNAMICS

The genus Acrocomia includes eight species, of which A. aculeata (Jacq.) Lodd. Ex Mart., A. intumescens Drude and A. totai Mart. are of economic interest. They have a high oil content and are native sources for food and biodiesel production. Next-generation sequencing technology has made it possible to obtain complete chloroplast sequences. This organelle is semi-autonomous, with its own genetic information, and is typically inherited uni-parentally, without recombination. We report the complete genomes of the chloroplasts of A. intumescens and A. totai. We were able to investigate: (1) gene content; (2) structural comparisons; (3) single sequence repeats (SSRs) and dispersed repeats; (4) RNA editing sites and (5) the evolution of the Arecaceae family in phylogeny with these genomes. The genomes had 156,590 bp (A. intumescens) and 156,604 bp (A. totai), a quadripartite structure with two single copies (large single copy-LSC and small single copy-SSC), and two inverted repeats (IRA and IRB). 85 protein-coding genes were identified, 8 rRNAs and 38 tRNAs. A high level of synteny was observed in Acrocomia compared to other palms and few rearrangements. However, expansions/contractions were identified in the IRs. In relation to SSRs, 72 and 69 were detected in A. intumescens and A. totai and 43 dispersed repeats in the two species. These values are usually conserved in palms of the same genus and are important phylogenetic information. Considering the RNA editing sites, 77 conversions were detected between the two species. Compared to Bactris gasipaes and Syagrus romanzoffiana, which belong to the same tribe, Cocoseae, 70 sites were shared. In the phylogeny, the species A. intumescens and A. totai were classified as sisters and then sisters to A. aculeata. A consolidated pattern was identified between the genomes, with subtle structural changes, and resources were provided for evolutionary analysis and conservation of the Arecaceae family.