Global Changes in Terrestrial Vegetation and Continental Climate During the Paleocene‐Eocene Thermal Maximum

Paleoceanography and Paleoclimatology, Journal Year: 2022, Volume and Issue: 37(4)

Published: April 1, 2022

Abstract Most studies of the response terrestrial vegetation to climate change during Paleocene‐Eocene Thermal Maximum (PETM) have focused on individual sites and sections. To get a broader perspective we compiled published records pollen spores across transition at 38 around globe. For 10 with quantitative data PETM palynofloras were largely distinct in composition from those latest Paleocene or post‐PETM early Eocene. We also inferred paleoclimatic conditions each site distributions nearest living relatives (NLRs) fossil taxa among present‐day Köppen types. The NLRs high‐paleolatitude palynotaxa are most diverse cooler climates, whereas more warmer, wetter climates. At middle‐paleolatitudes warm, wet seasonally dry In tropics there is little NLRs. compared changes paleoclimate reconstructed simulated Community Earth System Model (version CESM1.2). Paleoclimatic palynological proxies mostly consistent modeled changes, including expansion temperate climates expense cold types high‐paleolatitudes tropical middle‐paleolatitudes. Despite this concordance, winter temperatures continental interiors remain colder than NLR distributions.

Language: Английский

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The rise of grasslands is linked to atmospheric CO2 decline in the late Palaeogene

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Jan. 12, 2022

Abstract Grasslands are predicted to experience a major biodiversity change by the year 2100. A better understanding of how grasslands have responded past environmental changes will help predict outcome current and future changes. Here, we explore relationship between atmospheric CO 2 temperature fluctuations shifts in diversification rate Poaceae (grasses) Asteraceae (daisies), two exceptionally species-rich grassland families (~11,000 ~23,000 species, respectively). To this end, develop Bayesian approach that simultaneously estimates rates through time from time-calibrated phylogenies correlations variables rates. Additionally, present statistical incorporates information distribution missing species phylogeny. We find strong evidence supporting simultaneous increase for grasses daisies after most significant reduction Cenozoic (~34 Mya). The paleo-temperatures, however, appear not had with these families. Overall, our results shed new light on origin context

Language: Английский

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Genetic basis and dual adaptive role of floral pigmentation in sunflowers

eLife, Journal Year: 2022, Volume and Issue: 11

Published: Jan. 11, 2022

Variation in floral displays, both between and within species, has been long known to be shaped by the mutualistic interactions that plants establish with their pollinators. However, increasing evidence suggests abiotic selection pressures influence diversity as well. Here, we analyse genetic environmental factors underlie patterns of pigmentation wild sunflowers. While sunflower inflorescences appear invariably yellow human eye, they display extreme for ultraviolet pigmentation, which are visible most We show this is largely controlled cis-regulatory variation affecting a single MYB transcription factor, HaMYB111, through accumulation (UV)-absorbing flavonol glycosides ligules (the 'petals' inflorescences). Different pigments flowers strongly correlated pollinator preferences. Furthermore, associated variables, especially relative humidity, across populations Ligules larger patterns, found drier environments, increased resistance desiccation, suggesting role reducing water loss. The dual UV attraction response reveals complex adaptive balance underlying evolution traits.Flowers an important part how many reproduce. Their distinctive colours, shapes attract specific pollinators, but can also help protect plant from predators stresses. Many contain absorb (UV) light distinct – although invisible pollinators able see them. For example, when seen UV, sunflowers feature ‘bullseye’ dark centre surrounded reflective outer ring. sizes thicknesses these rings vary lot flower so far, it unclear what causes affects plants. To find out more, Todesco et al. studied various North America considering ecology molecular biology different This revealed great populations. Moreover, gene called HaMYB111 responsible diverse controls make chemicals flavonols light. Flavonols damage caused droughts temperatures. showed bullseyes had more flavonols, attracted were better at conserving water. Accordingly, locations. study that, least sunflowers, control These insights could improve pollination consequently yield cultivated plants, develop weather. work highlights importance combining on small large scales understand processes, such adaptation evolution.

Language: Английский

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Nuclear phylogenomics of Asteraceae with increased sampling provides new insights into convergent morphological and molecular evolution

Plant Communications, Journal Year: 2024, Volume and Issue: 5(6), P. 100851 - 100851

Published: Feb. 25, 2024

Convergent morphological evolution is widespread in flowering plants, and understanding this phenomenon relies on well-resolved phylogenies. Nuclear phylogenetic reconstruction using transcriptome datasets has been successful various angiosperm groups, but it limited to taxa with available fresh materials. Asteraceae are one of the two largest families important for both ecosystems human livelihood, having multiple examples convergent evolution. phylogenies have resolved relationships among most subfamilies many tribes, evolutionary questions regarding subtribes genera remain due sampling. Here we increased sampling transcriptomes genome skimming produced nuclear trees 706 species representing thirds recognized subtribes. Ancestral character supports events Asteraceae, gains losses bilateral floral symmetry correlated diversification some smaller respectively. The presence calyx-related pappus might especially success genera. Molecular analyses supporting likely contribution duplications MADS-box TCP regulatory genes innovations, including capitulum inflorescence bilaterally symmetric flowers, potentially promoting Asteraceae. Subsequent divergences reductions CYC2 gene expression related gain loss zygomorphic flowers. phylogenomic work greater taxon by GS reveals feasibility expanded DNA samples

Language: Английский

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Genomic insights into the evolution of flavonoid biosynthesis and O-methyltransferase and glucosyltransferase in Chrysanthemum indicum

Cell Reports, Journal Year: 2024, Volume and Issue: 43(2), P. 113725 - 113725

Published: Jan. 31, 2024

Flavonoids are a class of secondary metabolites widely distributed in plants. Regiospecific modification by methylation and glycosylation determines flavonoid diversity. A rare flavone glycoside, diosmin (luteolin-4'-methoxyl-7-O-glucosyl-rhamnoside), occurs Chrysanthemum indicum. How plants evolve new biosynthetic capacities remains elusive. Here, we assemble 3.11-Gb high-quality C. indicum genome with contig N50 value 4.39 Mb annotate 50,606 protein-coding genes. One (CiCOMT10) the tandemly repeated O-methyltransferase genes undergoes neofunctionalization, preferentially transferring methyl group to 4'-hydroxyl luteolin ortho-substituents form diosmetin. In addition, CiUGT11 (UGT88B3) specifically glucosylates 7-OH Next, construct one-pot cascade biocatalyst system combining CiCOMT10, CiUGT11, our previously identified rhamnosyltransferase, effectively producing over 80% conversion from luteolin. This study clarifies role transferases diversity provides important gene elements essential for flavone.

Language: Английский

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Sesquiterpene Lactones – Insights into Biosynthesis, Regulation and Signalling Roles

Critical Reviews in Plant Sciences, Journal Year: 2024, Volume and Issue: 43(3), P. 131 - 157

Published: Feb. 10, 2024

Sesquiterpene lactones (STLs) are bitter tasting plant specialized metabolites derived from farnesyl pyrophosphate (FPP) that contain a characteristic lactone ring. STLs can be found in many families distantly related to each other and outside the kingdom. They especially prevalent Apiaceae Asteraceae, latter being one of largest besides Orchidaceae. The STL diversity is large which made them an ideal object for chemosystematic studies these species. Many show high bioactivity, example as protective compounds against herbivory. also relevant pharmaceutical applications, such treatment malaria with artemisinin. Recent findings have dramatically changed our knowledge about biosynthesis STLs, well their developmental, spatial, environmental regulation. This review intents update currently achieved progress aspects. With advancement genome editing tools CRISPR/Cas rapid acceleration speed sequencing, even deeper insights into biosynthesis, regulation, enzyme evolution expected future. Apart role compounds, there may more subtle regulatory processes plants will discussed well.

Language: Английский

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Echinacea spp.: The cold-fighter herbal remedy?

Pharmacological Research - Modern Chinese Medicine, Journal Year: 2024, Volume and Issue: 10, P. 100397 - 100397

Published: Feb. 17, 2024

Language: Английский

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Prediction of the reaction mechanisms of sesquiterpene coumarin synthases supports a direct evolutionary link with triterpene biosynthesis

Phytochemistry Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 4, 2025

Language: Английский

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Convergent evidence for the temperature-dependent emergence of silicification in terrestrial plants

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 29, 2025

Abstract Research on silicon (Si) biogeochemistry and its beneficial effects for plants has received significant attention over several decades, but the reasons emergence of high-Si remain unclear. Here, we combine experimentation, field studies analysis existing databases to test role temperature expression silicification in terrestrial plants. We first show that Si is rice under high (40 °C), harmful low (0 whilst a 2 °C increase results 37% leaf concentrations. then find that, globally, average distribution plant clades 1.2 higher than low-Si clades. Across China, concentrations with (wheat rice), not (weeping willow winter jasmine). From an evolutionary perspective, 77% families (>10 mg g −1 DW) originate during warming episodes, while 86% (<1 cooling episodes. On average, Earth’s 3 families. Taken together, our evidence suggests variation closely related global long-term climate change.

Language: Английский

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Chromosome number variation and phylogenetic divergence of East Asian Cirsium sect. Onotrophe subsect. Nipponocirsium (Compositae), with a new species from Taiwan

Botanical studies, Journal Year: 2025, Volume and Issue: 66(1)

Published: Feb. 14, 2025

Abstract Background This study explored chromosome number variation, phylogenetic divergence, and mechanisms underlying speciation in East Asian thistle Cirsium Mill. sect. Onotrophe (Cass.) DC. subsect. Nipponocirsium Kitam. (Compositae). The focused on the newly identified species from Taiwan: pengii Y.H. Tseng, P.C. Liao & Chih Y. Chang. Utilizing phylotranscriptomic data to reconstruct evolutionary relationships between Taiwanese Japanese taxa of as well their divergence times chromosomal characteristics. Additionally, number, morphology, pollen morphology unknown taxon are compared with other known Taiwan. Results Phylotranscriptomic analysis reveals a division within into clades. In clade, C. is basal, while tatakaense remains monophyletic despite higher genetic diversity. prevalent this subsection tetraploid (2 n = 4 x 68), common taxa, members have 2 64. Notably, has diploid 32), indicating descending dysploidy followed by polyploidization polyploidization, driven glaciations, likely shaped evolution . Divergence time estimates suggest separation clades around 0.74 million years ago (Myr) during glacial periods. diverged 0.47 Myr, kawakamii 0.35 Myr. These evolved separate refugia, distinct boundaries confirmed through delimitation analysis, karyotype, comparisons. Conclusions findings enhance our understanding underscore importance integrating transcriptomic studies. provides comprehensive framework for further investigations diversity adaptive ecologically vital group.

Language: Английский

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