Genlisea hawkingii (Lentibulariaceae), a new species from Serra da Canastra, Minas Gerais, Brazil

The phylogenomics and evolutionary dynamics of the organellar genomes in carnivorous Utricularia and Genlisea species (Lentibulariaceae)

Utricularia and Genlisea are highly specialized carnivorous plants whose phylogenetic history has been poorly explored using phylogenomic methods. Additional sampling and genomic data are needed to advance our phylogenetic and taxonomic knowledge of this group of plants. Within a comparative framework, we present a characterization of plastome (PT) and mitochondrial (MT) genes of 26 Utricularia and six Genlisea species, with representatives of all subgenera and growth habits. All PT genomes maintain similar gene content, showing minor variation across the genes located between the PT junctions. One exception is a major variation related to different patterns in the presence and absence of ndh genes in the small single copy region, which appears to follow the phylogenetic history of the species rather than their lifestyle. All MT genomes exhibit similar gene content, with most differences related to a lineage-specific pseudogenes. We find evidence for episodic positive diversifying selection in PT and for most of the Utricularia MT genes that may be related to the current hypothesis that bladderworts' nuclear DNA is under constant ROS oxidative DNA damage and unusual DNA repair mechanisms, or even low fidelity polymerase that bypass lesions which could also be affecting the organellar genomes. Finally, both PT and MT phylogenetic trees were well resolved and highly supported, providing a congruent phylogenomic hypothesis for Utricularia and Genlisea clade given the study sampling.

The complete mitochondrial genome of carnivorous Genlisea tuberosa (Lentibulariaceae): Structure and evolutionary aspects

Sequenced genomic data for carnivorous plants are scarce, especially regarding the mitogenomes (MTs) and further studies are crucial to obtain a better understanding of the topic. In this study, we sequenced and characterized the mitochondrial genome of the tuberous carnivorous plant Genlisea tuberosa, being the first of its genus to be sequenced. The genome comprises 729,765 bp, encoding 80 identified genes of which 36 are protein-coding, 40 tRNA, four rRNA genes, and three pseudogenes. An intronic region from the cox1 gene was identified that encodes an endonuclease enzyme that is present in the other sequenced species of Lentibulariaceae. Chloroplast genes (pseudogene and complete) inserted in the MT genome were identified, showing possible horizontal transfer between organelles. In addition, 50 pairs of long repeats from 94 to 274 bp are present, possibly playing an important role in the maintenance of the MT genome. Phylogenetic analysis carried out with 34 coding mitochondrial genes corroborated the positioning of the species listed here within the family. The molecular dynamism in the mitogenome (e.g. the loss or pseudogenization of genes, insertion of foreign genes, the long repeats as well as accumulated mutations) may be reflections of the carnivorous lifestyle where a significant part of cellular energy was shifted for the adaptation of leaves into traps molding the mitochondrial DNA. The sequence and annotation of G. tuberosa's MT will be useful for further studies and serve as a model for evolutionary and taxonomic clarifications of the group as well as improving our comprehension of MT evolution.