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Vogt, R.

Publications and source records attributed to Vogt, R..

3 recordsLinked to original sources

Why woodiness repeatedly evolves--and disappears

Derived woodiness--the evolution of woody growth from herbaceous ancestors--has arisen hundreds of times across flowering plants, yet the environmental conditions associated with its repeated evolution remain poorly understood. Here, we analyse woodiness evolution in the mustard family (Brassicaceae; ~4,150 species) using a time-calibrated phylogeny of 2,927 species, including 374 of the 385 known woody species, together with global growth-form and climatic niche data. We infer 231 independent origins of woodiness alongside 176 reversals to herbaceousness, indicating that woodiness evolves repeatedly but remains evolutionarily unstable. Although woody species are enriched on islands, most occur on the mainland, where woodiness is consistently associated with drought and reduced frost. Correlated-evolution analyses reveal that drought is associated primarily with the persistence of woodiness, whereas reduced frost is associated with gains of woodiness and increased frost with its loss. These findings identify distinct climatic associations with the gain, persistence, and loss of woody growth forms.

evolutionary biology↗

Global Phylogeny of the Brassicaceae Provides Important Insights into Gene Discordance

The mustard family (Brassicaceae) is a scientifically and economically important family, containing the model plant Arabidopsis thaliana and numerous crop species that feed billions worldwide. Despite its relevance, most published family phylogenies are incompletely sampled, generally contain massive polytomies, and/or show incongruent topologies between datasets. Here, we present the most complete Brassicaceae genus-level family phylogenies to date (Brassicaceae Tree of Life, or BrassiToL) based on nuclear (>1,000 genes, almost all 349 genera and 53 tribes) and plastome (60 genes, 79% of the genera, all tribes) data. We found cytonuclear discordance between nuclear and plastome-derived phylogenies, which is likely a result of rampant hybridisation among closely and more distantly related species, and highlight rogue taxa. To evaluate the impact of this rampant hybridisation on the nuclear phylogeny reconstruction, we performed four different sampling routines that increasingly removed variable data and likely paralogs. Our resulting cleaned subset of 297 nuclear genes revealed high support for the tribes, while support for the main lineages remained relatively low. Calibration based on the 20 most clock-like nuclear genes suggests a late Eocene to late Oligocene icehouse origin of the family. Finally, we propose five new or re-established tribes, including the recognition of Arabidopsideae, a monotypic tribe to accommodate Arabidopsis. With a worldwide community of thousands of researchers working on this family, our new, densely sampled family phylogeny will be an indispensable tool to further highlight Brassicaceae as an excellent model family for studies on biodiversity and plant biology.

evolutionary biology↗

An evolutionary approach to systematic discovery of novel deubiquitinases, applied to Legionella

Deubiquitinating enzymes (DUBs) are important regulators of the posttranslational protein ubiquitination system. Mammalian genomes encode about hundred different DUBs, which can be grouped into seven different classes. Members of other DUB classes are found in pathogenic bacteria, which use them to target the host defense. By combining bioinformatical and experimental approaches, we address the question if the known DUB families have a common evolutionary ancestry and share conserved features that set them apart from other proteases. By systematically comparing family-specific Hidden-Markov-Models, we uncovered distant relationships between established DUBs and other cysteine protease families. Most DUB families share a conserved aromatic residue linked to the active site, which restricts the cleavage of substrates with sidechains at the S2 position, corresponding to Gly-75 in ubiquitin. By applying these criteria to Legionella pneumophila ORFs, we identified lpg1621 and lpg1148 as deubiquitinases, characterized their cleavage specificities, and confirmed the importance of the aromatic gatekeeper motif for substrate selection.Competing Interest StatementThe authors have declared no competing interest.View Full Text

biochemistry↗