Phylogenomic Analyses of Nuclear Genes Reveal the Evolutionary Relationships within the BEP Clade and the Evidence of Positive Selection in Poaceae

Abstract Many cytoskeletal proteins perform fundamental biological processes and are evolutionarily ancient. For example, the superfamily of actin-related proteins (Arps) specialized early in eukaryotic evolution for diverse cellular roles in the cytoplasm and the nucleus. Despite its strict conservation across eukaryotes, we find that the Arp superfamily has undergone dramatic lineage-specific diversification in Drosophila. Our phylogenomic analyses reveal four independent Arp gene duplications that occurred in the common ancestor of the obscura group of Drosophila and have been mostly preserved in this lineage. All four obscura-specific Arp paralogs are predominantly expressed in the male germline and have evolved under positive selection. We focus our analyses on the divergent Arp2D paralog, which arose via a retroduplication event from Arp2, a component of the Arp2/3 complex that polymerizes branched actin networks. Computational modeling analyses suggest that Arp2D can replace Arp2 in the Arp2/3 complex and bind actin monomers. Together with the signature of positive selection, our findings suggest that Arp2D may augment Arp2’s functions in the male germline. Indeed, we find that Arp2D is expressed during and following male meiosis, where it localizes to distinct locations such as actin cones—specialized cytoskeletal structures that separate bundled spermatids into individual mature sperm. We hypothesize that this unprecedented burst of genetic innovation in cytoskeletal proteins may have been driven by the evolution of sperm heteromorphism in the obscura group of Drosophila.

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Genome-wide signatures of plastid-nuclear coevolution point to repeated perturbations of plastid proteostasis systems across angiosperms

The Plant Cell ◽

10.1093/plcell/koab021 ◽

2021 ◽

Author(s):

Evan S Forsythe ◽

Alissa M Williams ◽

Daniel B Sloan

Keyword(s):

Nuclear Genome ◽

Protein Translation ◽

Nuclear Genes ◽

Sequence Evolution ◽

Cellular Functions ◽

Transmission Modes ◽

Chloroplast Genomes ◽

Genome Wide ◽

Genes Encoding ◽

Phylogenomic Analyses

Abstract Nuclear and plastid (chloroplast) genomes experience different mutation rates, levels of selection, and transmission modes, yet key cellular functions depend on their coordinated interactions. Functionally related proteins often show correlated changes in rates of sequence evolution across a phylogeny (evolutionary rate covariation or ERC), offering a means to detect previously unidentified suites of coevolving and cofunctional genes. We performed phylogenomic analyses across angiosperm diversity, scanning the nuclear genome for genes that exhibit ERC with plastid genes. As expected, the strongest hits were highly enriched for genes encoding plastid-targeted proteins, providing evidence that cytonuclear interactions affect rates of molecular evolution at genome-wide scales. Many identified nuclear genes functioned in post-transcriptional regulation and the maintenance of protein homeostasis (proteostasis), including protein translation (in both the plastid and cytosol), import, quality control and turnover. We also identified nuclear genes that exhibit strong signatures of coevolution with the plastid genome, but their encoded proteins lack organellar-targeting annotations, making them candidates for having previously undescribed roles in plastids. In sum, our genome-wide analyses reveal that plastid-nuclear coevolution extends beyond the intimate molecular interactions within chloroplast enzyme complexes and may be driven by frequent rewiring of the machinery responsible for maintenance of plastid proteostasis in angiosperms.

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Allele Sorting as a Novel Approach to Resolving the Origin of Allotetraploids Using Hyb-Seq Data: A Case Study of the Balkan Mountain Endemic Cardamine barbaraeoides

Frontiers in Plant Science ◽

10.3389/fpls.2021.659275 ◽

2021 ◽

Vol 12 ◽

Author(s):

Marek Šlenker ◽

Adam Kantor ◽

Karol Marhold ◽

Roswitha Schmickl ◽

Terezie Mandáková ◽

...

Keyword(s):

Phylogenetic Reconstruction ◽

Balkan Peninsula ◽

Nuclear Genes ◽

Nuclear Ribosomal Dna ◽

Interspecific Gene Flow ◽

Polyploid Evolution ◽

Pleistocene Climate ◽

Novel Approach ◽

The Rich ◽

Phylogenomic Analyses

Mountains of the Balkan Peninsula are significant biodiversity hotspots with great species richness and a large proportion of narrow endemics. Processes that have driven the evolution of the rich Balkan mountain flora, however, are still insufficiently explored and understood. Here we focus on a group of Cardamine (Brassicaceae) perennials growing in wet, mainly mountainous habitats. It comprises several Mediterranean endemics, including those restricted to the Balkan Peninsula. We used target enrichment with genome skimming (Hyb-Seq) to infer their phylogenetic relationships, and, along with genomic in situ hybridization (GISH), to resolve the origin of tetraploid Cardamine barbaraeoides endemic to the Southern Pindos Mts. (Greece). We also explored the challenges of phylogenomic analyses of polyploid species and developed a new approach of allele sorting into homeologs that allows identifying subgenomes inherited from different progenitors. We obtained a robust phylogenetic reconstruction for diploids based on 1,168 low-copy nuclear genes, which suggested both allopatric and ecological speciation events. In addition, cases of plastid–nuclear discordance, in agreement with divergent nuclear ribosomal DNA (nrDNA) copy variants in some species, indicated traces of interspecific gene flow. Our results also support biogeographic links between the Balkan and Anatolian–Caucasus regions and illustrate the contribution of the latter region to high Balkan biodiversity. An allopolyploid origin was inferred for C. barbaraeoides, which highlights the role of mountains in the Balkan Peninsula both as refugia and melting pots favoring species contacts and polyploid evolution in response to Pleistocene climate-induced range dynamics. Overall, our study demonstrates the importance of a thorough phylogenomic approach when studying the evolution of recently diverged species complexes affected by reticulation events at both diploid and polyploid levels. We emphasize the significance of retrieving allelic and homeologous variation from nuclear genes, as well as multiple nrDNA copy variants from genome skim data.

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Multispecies coalescent analysis unravels the non-monophyly and controversial relationships of Hexapoda

10.1101/187997 ◽

2017 ◽

Author(s):

Lucas A. Freitas ◽

Beatriz Mello ◽

Carlos G. Schrago

Keyword(s):

Phylogenetic Relationships ◽

Gene Tree ◽

Genomic Data ◽

Population Level ◽

Phylogenetic Inference ◽

Evolutionary Relationships ◽

Effective Population ◽

Multispecies Coalescent ◽

Population Sizes ◽

Phylogenomic Analyses

AbstractWith the increase in the availability of genomic data, sequences from different loci are usually concatenated in a supermatrix for phylogenetic inference. However, as an alternative to the supermatrix approach, several implementations of the multispecies coalescent (MSC) have been increasingly used in phylogenomic analyses due to their advantages in accommodating gene tree topological heterogeneity by taking account population-level processes. Moreover, the development of faster algorithms under the MSC is enabling the analysis of thousands of loci/taxa. Here, we explored the MSC approach for a phylogenomic dataset of Insecta. Even with the challenges posed by insects, due to large effective population sizes coupled with short deep internal branches, our MSC analysis could recover several orders and evolutionary relationships in agreement with current insect systematics. However, some phylogenetic relationships were not recovered by MSC methods. Most noticeable, a remiped crustacean was positioned within the Insecta. Additionally, the interordinal relationships within Polyneoptera and Neuropteroidea contradicted recent works, by suggesting the non-monophyly of Neuroptera. We notice, however, that these phylogenetic arrangements were also poorly supported by previous analyses and that they were sensitive to gene sampling.

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Faculty Opinions recommendation of Phylogenomic analyses elucidate the evolutionary relationships of bats.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718164045.793493035 ◽

2014 ◽

Author(s):

Anthony Michael Carter

Keyword(s):

Evolutionary Relationships ◽

Phylogenomic Analyses

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Phylogenomic Analyses Elucidate the Evolutionary Relationships of Bats

Current Biology ◽

10.1016/j.cub.2013.09.014 ◽

2013 ◽

Vol 23 (22) ◽

pp. 2262-2267 ◽

Cited By ~ 87

Author(s):

Georgia Tsagkogeorga ◽

Joe Parker ◽

Elia Stupka ◽

James A. Cotton ◽

Stephen J. Rossiter

Keyword(s):

Evolutionary Relationships ◽

Phylogenomic Analyses

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Widespread paleopolyploidy, gene tree conflict, and recalcitrant relationships among the carnivorous Caryophyllales

10.1101/115741 ◽

2017 ◽

Cited By ~ 1

Author(s):

Joseph F. Walker ◽

Ya Yang ◽

Michael J. Moore ◽

Jessica Mikenas ◽

Alfonso Timoneda ◽

...

Keyword(s):

Gene Tree ◽

West African ◽

Evolutionary Relationships ◽

Taxon Sampling ◽

Data Sets ◽

List Type ◽

Data Set ◽

Present Evidence ◽

Gene Tree Discordance ◽

Phylogenomic Analyses

ABSTRACTThe carnivorous members of the large, hyperdiverse Caryophyllales (e.g. Venus flytrap, sundews and Nepenthes pitcher plants) represent perhaps the oldest and most diverse lineage of carnivorous plants. However, despite numerous studies seeking to elucidate their evolutionary relationships, the early-diverging relationships remain unresolved.To explore the utility of phylogenomic data sets for resolving relationships among the carnivorous Caryophyllales, we sequenced ten transcriptomes, including all the carnivorous genera except those in the rare West African liana family (Dioncophyllaceae). We used a variety of methods to infer the species tree, examine gene tree conflict and infer paleopolyploidy events.Phylogenomic analyses support the monophyly of the carnivorous Caryophyllales, with an origin of 68-83 mya. In contrast to previous analyses recover the remaining non-core Caryophyllales as non-monophyletic, although there are multiple reasons this result may be spurious and node supporting this relationship contains a significant amount gene tree discordance. We present evidence that the clade contains at least seven independent paleopolyploidy events, previously debated nodes from the literature have high levels of gene tree conflict, and taxon sampling influences topology even in a phylogenomic data set.Our data demonstrate the importance of carefully considering gene tree conflict and taxon sampling in phylogenomic analyses. Moreover, they provide a remarkable example of the propensity for paleopolyploidy in angiosperms, with at least seven such events in a clade of less than 2500 species.

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Comparative Analyses of Euonymus Chloroplast Genomes: Genetic Structure, Screening for Loci With Suitable Polymorphism, Positive Selection Genes, and Phylogenetic Relationships Within Celastrineae

Frontiers in Plant Science ◽

10.3389/fpls.2020.593984 ◽

2021 ◽

Vol 11 ◽

Author(s):

Yongtan Li ◽

Yan Dong ◽

Yichao Liu ◽

Xiaoyue Yu ◽

Minsheng Yang ◽

...

Keyword(s):

Positive Selection ◽

Chloroplast Genome ◽

Gc Content ◽

Single Copy ◽

Rrna Genes ◽

Evolutionary Relationships ◽

Trna Genes ◽

Protein Coding ◽

Chloroplast Genomes ◽

Cp Genome

In this study, we assembled and annotated the chloroplast (cp) genome of the Euonymus species Euonymus fortunei, Euonymus phellomanus, and Euonymus maackii, and performed a series of analyses to investigate gene structure, GC content, sequence alignment, and nucleic acid diversity, with the objectives of identifying positive selection genes and understanding evolutionary relationships. The results indicated that the Euonymus cp genome was 156,860–157,611bp in length and exhibited a typical circular tetrad structure. Similar to the majority of angiosperm chloroplast genomes, the results yielded a large single-copy region (LSC) (85,826–86,299bp) and a small single-copy region (SSC) (18,319–18,536bp), separated by a pair of sequences (IRA and IRB; 26,341–26,700bp) with the same encoding but in opposite directions. The chloroplast genome was annotated to 130–131 genes, including 85–86 protein coding genes, 37 tRNA genes, and eight rRNA genes, with GC contents of 37.26–37.31%. The GC content was variable among regions and was highest in the inverted repeat (IR) region. The IR boundary of Euonymus happened expanding resulting that the rps19 entered into IR region and doubled completely. Such fluctuations at the border positions might be helpful in determining evolutionary relationships among Euonymus. The simple-sequence repeats (SSRs) of Euonymus species were composed primarily of single nucleotides (A)n and (T)n, and were mostly 10–12bp in length, with an obvious A/T bias. We identified several loci with suitable polymorphism with the potential use as molecular markers for inferring the phylogeny within the genus Euonymus. Signatures of positive selection were seen in rpoB protein encoding genes. Based on data from the whole chloroplast genome, common single copy genes, and the LSC, SSC, and IR regions, we constructed an evolutionary tree of Euonymus and related species, the results of which were consistent with traditional taxonomic classifications. It showed that E. fortunei sister to the Euonymus japonicus, whereby E. maackii appeared as sister to Euonymus hamiltonianus. Our study provides important genetic information to support further investigations into the phylogenetic development and adaptive evolution of Euonymus species.

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