Adaptive Diversity Research Articles

Sonic hedgehog and fibroblast growth factor 8 regulate the evolution of amniote facial proportions

Amniote skulls are diverse in shape and skeletal composition, which is the basis of much adaptive diversification within this clade. Major differences in skull shape are established early in development, at a critical developmental interval spanning the initial outgrowth and fusion of the facial processes. In birds, this is orchestrated by domains of Shh and Fgf8 expression, known as the frontonasal ectodermal zone (FEZ). It is unclear whether this model of facial development applies to species with diverse facial skeletons, especially species possessing a skull morphology representative of early amniotes. By investigating facial morphogenesis in the lizard, Anolis sagrei, we show that reptilian skull development is driven by the same genes as mammals and birds, but the manner in which those genes regulate facial development is clade-specific. These genes are not expressed in the frontal-nasal prominence, the region of the avian FEZ. Downregulating Shh and Fgf8 signaling disrupts normal facial development, but in pathway-specific ways. Our results demonstrate that early facial morphogenesis in lizards does not conform to the FEZ model. Lizard skull development may be more representative of the ancestral amniote than other model species with highly derived facial skeletons suggesting that the FEZ may be an avian-specific novelty.

Walking or hanging: the role of habitat use for body shape evolution in lacertid lizards.

Differences in habitat use impose ecological constraints which in turn lead to functional and morphological differences through adaptation. In fact, a convergent evolutionary pattern is evident when species exhibit similar responses to similar environments. In this study we examine how habitat use influences the evolution of body shape in lizards from the family Lacertidae. We divided our species set into two categories: ground-dwellers and climbers, which encompasses the verticality and horizontality aspects of the habitat. We performed phylogenetic comparative analyses employing 186 species and seven linear morphological traits. Our results show contrasting patterns between head and limb shape, which are considered distinct functional blocks. We observed differences in forelimb proportions, but not in hindlimb length, contrary to what was documented in other lizard groups, demonstrating a novel axis in the limb-locomotion-habitat relationship in this family. In addition, a clear effect of habitat use on head shape was detected. We observed that climbing species present on average flatter heads than ground-dwelling species, as well as different evolutionary trajectories. These findings suggest the complex interplay between habitat use and morphological evolution in lizards, highlighting how distinct selective pressures drive divergent adaptations in different functional traits.

Slight thermal stress exerts genetic diversity selection at coral (Acropora digitifera) larval stages

BackgroundRising seawater temperatures increasingly threaten coral reefs. The ability of coral larvae to withstand heat is crucial for maintaining reef ecosystems. Although several studies have investigated coral larvae’s genetic responses to thermal stress, most relied on pooled sample sequencing, which provides population-level insights but may mask individual genotype variability. This study uses individual larval sequencing to investigate genotype-specific responses to heat stress and the selective pressures shaping their genomes, offering finer resolution and deeper insights.ResultsThis study investigates the larval response to heat stress before acquiring symbiotic algae, aiming to elucidate the relationship between coral genetic diversity and heat stress. Larvae sourced from eight Acropora digitifera colonies were subjected to ambient temperature (28 °C) and heat conditions (31 °C). The impact of heat stress on larval genetic diversity was assessed through sequencing. While overall genetic diversity, represented by π, did not significantly differ between the control and heat-exposed groups, Tajima’s D differed, indicating different selective pressures in each group. The genomic regions under higher and lower Tajima’s D were not broadly shared among control and head conditions, implying that selective pressures operated in distinctive manners. Many larval protein-coding sequences were identified in this genomic region, and the codon evolution of many of these genes showed signs of positive selection. These results highlight the complex selective pressures on coral larvae under different temperatures. The genes showing signs of positive selection in response to heat stress may have also been influenced by historical temperature fluctuations, as suggested by their association with loci identified during Acroporid speciation. These loci under codon-level positive selection during speciation highlight the potential role of genetic diversity in shaping adaptation to environmental changes over evolutionary timescales.ConclusionThese findings underscore the significance of genetic diversity in coral reproduction for maintaining reef ecosystems. They also indicate that even minor heat stress can exert significant selective pressure, potentially leading to profound implications for coral reef ecosystems. This research is crucial for understanding the impact of rising seawater temperatures on coral reefs.

Generalized Adaptive Diversity Gradient Descent Bit-Flipping with a Finite State Machine.

In this paper, we introduce a novel gradient descent bit-flipping algorithm with a finite state machine (GDBF-wSM) for iterative decoding of low-density parity-check (LDPC) codes. The algorithm utilizes a finite state machine to update variable node potentials-for each variable node, the corresponding finite state machine adjusts the update value based on whether the node was a candidate for flipping in previous iterations. We also present a learnable framework that can optimize decoder parameters using a database of uncorrectable error patterns. The performance of the proposed algorithm is illustrated for various regular LDPC codes, both in a binary symmetric channel (BSC) and the channel with additive white Gaussian noise (AWGN). The numerical results indicate a performance improvement when comparing our algorithm to previously proposed GDBF-based approaches.

Response of Pedunculate Oak (Quercus robur L.) to Adverse Environmental Conditions in Genetic and Dendrochronological Studies.

Pedunculate oak (Quercus robur L.) is widely distributed across Europe and serves critical ecological, economic, and recreational functions. Investigating its responses to stressors such as drought, extreme temperatures, pests, and pathogens provides valuable insights into its capacity to adapt to climate change. Genetic and dendrochronological studies offer complementary perspectives on this adaptability. Tree-ring analysis (dendrochronology) reveals how Q. robur has historically responded to environmental stressors, linking growth patterns to specific conditions such as drought or temperature extremes. By examining tree-ring width, density, and dynamics, researchers can identify periods of growth suppression or enhancement and predict forest responses to future climatic events. Genetic studies further complement this by uncovering adaptive genetic diversity and inheritance patterns. Identifying genetic markers associated with stress tolerance enables forest managers to prioritize the conservation of populations with higher adaptive potential. These insights can guide reforestation efforts and support the development of climate-resilient oak populations. By integrating genetic and dendrochronological data, researchers gain a holistic understanding of Q. robur's mechanisms of resilience. This knowledge is vital for adaptive forest management and sustainable planning in the face of environmental challenges, ultimately helping to ensure the long-term viability of oak populations and their ecosystems. The topics covered in this review are very broad. We tried to include the most relevant, important, and significant studies, but focused mainly on the relatively recent Eastern European studies because they include the most of the species' area. However, although more than 270 published works have been cited in this review, we have, of course, missed some published studies. We apologize in advance to authors of those relevant works that have not been cited.

Temperature Overshoot Would Have Lasting Impacts on Hydrology and Water Resources

AbstractModels of climate change impacts could be missing significant risks to hydrologic and water infrastructure systems through a shared feature: the idea that temperatures rise monotonically. By contrast, temperature overshoot pathways describe non‐monotonic warming trajectories, in which global temperatures first exceed a given target before declining to that target. Risks from overshoot pathways are qualitatively different from risks associated with monotonic warming trajectories, and are likely underestimated in current research and policy. Models suggest overshoot may be almost unavoidable if the more stringent Paris Agreement target limiting warming to 1.5°C over preindustrial levels is to be met by 2100. While overshoot has been relatively widely described in the climate literature, the impacts of overshoot on individual system characteristics have not. We suggest that failure to consider disparities between monotonic and overshoot warming impacts on hydrology and water resources presents particular risks due to divergent adaptation needs. Processes with decadal hysteresis are especially vulnerable. These include glacial contributions to streamflow; hydrologic consequences of vegetation change; altered groundwater; higher water use for fossil fuel combustion and carbon dioxide removal; and water infrastructure and policy that depends on climate conditions. We argue that risks of overshoot cannot be fully captured in current integrated assessment models and that overshoot needs to be specifically evaluated to adequately characterize risk in the water system. We consider how current modeling tools could be adapted to evaluate overshoot consequences, but also recognize that decisions must be made even without perfect knowledge.

Unveiling MHC-DAB Polymorphism Within the Western Balkan Salmonid Hotspot: Preliminary Outcomes from Native Trouts of Ohrid Lake and the Drin-Skadar Drainage (Albania).

Due to their involvement in pathogen-mediated immune responses, the hypervariable genes of the Major Histocompatibility Complex (MHC) have become a paradigm for investigating the evolution and maintenance of genetic (adaptive) diversity, contextually providing insight into the viability of wild populations, which is meaningful for conservation. Here, we provide the first preliminary characterization of MHC polymorphism and evolution in trouts from Albania, a known hotspot of Salmonid diversity harboring ecologically and phylogenetically distinct native (threatened) taxa. Overall, 36 trout-including Lake Ohrid-endemic Salmo ohridanus and S. letnica, and both riverine and lacustrine native brown trout (the S. trutta complex) from the Drin-Skadar drainage-were genotyped at the MHC-DAB locus through next-generation amplicon sequencing. We identified 34 alleles (including 30 novel alleles), unveiling remarkable population/taxon MHC-DAB distinctiveness. Despite apparent functional (supertype) similarity, S. letnica and the S. trutta complex showed MHC-typical high sequence/allele diversity and evidence of global/codon-specific positive selection, particularly at antigen-binding sites. Conversely, deep-water-adapted S. ohridanus revealed unexpectedly reduced allelic/supertype diversity and relaxed selection. Evolution by reticulation and signals of trans-species polymorphism emerged from sequence genealogies. Further investigations and increased sampling will provide a deeper understanding of the evolutionary mechanisms yielding the observed pattern of MHC diversity across Albanian trout taxa and populations.

Genetic Assessment and Positioning of Algerian Barley Landraces with Respect to Landraces from the Middle East and Europe Using RAPD and SSR Markers.

Landraces are a critical genetic resource for resilience breeding, offering solutions to prepare agriculture for the challenges posed by climate change. Their efficient utilisation depends on understanding their history and genetic relationships. The current study investigates the phylogenetic relationships of barley landraces from Algeria, varieties from the Near and Middle East, traditional landraces, and modern cultivars from Europe. Using a core set of 33 varieties, including the wild ancestor Hordeum spontaneum from Armenia, genetic diversity was analysed with Random Amplified Polymorphic DNA (RAPD) and Simple Sequence Repeat (SSR) markers spanning all barley chromosomes. Based on the SSR-based phylogeny, the Algerian varieties are well clustered with those from the Near East, while distinct from the European varieties. The findings from RAPD markers partially support these results. Using exclusively traditional landraces, where a region of origin can be defined, the SSR markers are analysed separately for each chromosome individually, and the resulting clades are represented by the respective region of origin. This strategy resolves qualitative differences in geographic resolution, depending on the chromosome. While marker HvB23D (chromosome 4) separated the wild H. spontaneum from all domesticated genotypes, markers Bmag19 and Hv13GIII (chromosome 3) reveal four distinct geographic clusters (Maghreb, Near and Middle East, West Europe, Central Europe). These biogeographic patterns suggest a model, where divergence of domesticated barley due to human activity interacted with introgression of individual chromosomes from wild barley, yielding adaptive diversity. These biogeographic patterns suggest a model in which the divergence of domesticated barley, driven by human activity, interacts with the introgression of chromosomes from wild barley, resulting in the creation of adaptive genetic diversity. Our research advances our knowledge of barley landraces' functional genomics and highlights their potential in molecular breeding, particularly for developing resilient varieties suited to diverse environmental conditions.

Maladaptation in cereal crop landraces following a soot-producing climate catastrophe.

Aerosol-producing global catastrophes such as nuclear war, super-volcano eruption, or asteroid strike, although rare, pose a serious threat to human survival. Light-absorbing aerosols would sharply reduce temperature and solar radiation reaching the earth's surface, decreasing crop productivity including for locally adapted traditional crop varieties, i.e. landraces. Here, we test post-catastrophic climate impacts on barley, maize, rice, and sorghum, four crops with extensive landrace cultivation, under a range of nuclear war scenarios that differ in the amount of soot injected into the climate model. We used a crop growth model to estimate gradients of environmental stressors that drive local adaptation. We then fit genotype environment associations using high density genomic markers with gradient forest offset (GF offset) methods and predicted maladaptation through time. As a validation, we found that our GF models successfully predicted local adaptation of maize landraces in multiple common gardens across Mexico. We found strong concordance between GF offset and disruptions in climate, and landraces were predicted to be the most maladapted across space and time where soot-induced climate change was the greatest. We further used our GF models to identify landrace varieties best matched to specific post-catastrophic conditions, indicating potential substitutions for agricultural resilience. We found the best landrace genotype was often far away or in another nation, though countries with more climatic diversity had better within-country substitutions. Our results highlight that a soot-producing catastrophe would result in the global maladaptation of landraces and suggest that current landrace adaptive diversity is insufficient for agricultural resilience in the case of the scenarios with the greatest change to climate.

Whole-genome resequencing to investigate the genetic diversity and mechanisms of plateau adaptation in Tibetan sheep

IntroductionTibetan sheep, economically important animals on the Qinghai–Tibet Plateau, have diversified into numerous local breeds with unique characteristics through prolonged environmental adaptation and selective breeding. However, most current research focuses on one or two breeds, and lacks a comprehensive representation of the genetic diversity across multiple Tibetan sheep breeds. This study aims to fill this gap by investigating the genetic structure, diversity and high-altitude adaptation of 6 Tibetan sheep breeds using whole-genome resequencing data.ResultsSix Tibetan sheep breeds were investigated in this study, and whole-genome resequencing data were used to investigate their genetic structure and population diversity. The results showed that the 6 Tibetan sheep breeds exhibited distinct separation in the phylogenetic tree; however, the levels of differentiation among the breeds were minimal, with extensive gene flow observed. Population structure analysis broadly categorized the 6 breeds into 3 distinct ecological types: plateau-type, valley-type and Euler-type. Analysis of unique single-nucleotide polymorphisms (SNPs) and selective sweeps between Argali and Tibetan sheep revealed that Tibetan sheep domestication was associated primarily with sensory and signal transduction, nutrient absorption and metabolism, and growth and reproductive characteristics. Finally, comprehensive analysis of selective sweep and transcriptome data suggested that Tibetan sheep breeds inhabiting different altitudes on the Qinghai–Tibet Plateau adapt by enhancing cardiopulmonary function, regulating body fluid balance through renal reabsorption, and modifying nutrient digestion and absorption pathways.ConclusionIn this study, we investigated the genetic diversity and population structure of 6 Tibetan sheep breeds in Qinghai Province, China. Additionally, we analyzed the domestication traits and investigated the unique adaptation mechanisms residing varying altitudes in the plateau region of Tibetan sheep. This study provides valuable insights into the evolutionary processes of Tibetan sheep in extreme environments. These findings will also contribute to the preservation of genetic diversity and offer a foundation for Tibetan sheep diversity preservation and plateau animal environmental adaptation mechanisms.

Chromosomal-Level Genome Suggests Adaptive Constraints Leading to the Historical Population Decline in an Extremely Endangered Plant.

Increased human activity and climate change have significantly impacted wild habitats and increased the number of endangered species. Exploring evolutionary history and predicting adaptive potential using genomic data will facilitate species conservation and biodiversity recovery. Here, we examined the genome evolution of a critically endangered tree Pellacalyx yunnanensis, a plant species with extremely small populations (PSESP) that is narrowly distributed in Xishuangbanna, China. The species has neared extinction due to economic exploitation in recent decades. We assembled a chromosome-level genome of 334 Mb, with the N50 length of 20.5 Mb. Using the genome, we discovered that P. yunnanensis has undergone several population size reductions, leading to excess deleterious mutations. The species may possess low adaptive potential due to reduced genetic diversity and the loss of stress-responsive genes. We estimate that P. yunnanensis is the basal species of its genus and diverged from its relatives during global cooling, suggesting it was stranded in unsuitable environments during periods of dramatic climate change. In particular, the loss of seed dormancy leads to germination under unfavourable conditions and reproduction challenges. This dormancy loss may have occurred through genetic changes that suppress ABA signalling and the loss of genes involved in seed maturation. The high-quality genome has also enabled us to reveal phenotypic trait evolution in Rhizophoraceae and identify divergent adaptation to intertidal and inland habitats. In summary, our study elucidates mechanisms underlying the decline and evaluates the adaptive potential of P. yunnanensis to future climate change, informing future conservation efforts.

Genomic insights into climate change-induced forest dieback in Abies alba hotspots of decline

AbstractUnderstanding adaptive genetic responses to climate change is an issue of utmost importance to improve conservation policies and adaptive management. This study deeps on it, focusing on rear-edge silver fir (Abies alba) forests, where decline has been reported and linked to climatic stressors, such as warming and recurrent drought events. Hotspots and coldspots of forest decline and mortality were defined. Different sets of single nucleotide polymorphisms (SNPs), namely genome-wide and adaptive, were used to study their genetic characteristics, aiming to identify differences in genetic diversity between vigor classes (declining and non-declining trees) and age cohorts (adult trees and saplings). Global DNA methylation levels were assessed to investigate a possible role of epigenetic processes in adaptation to stressful environments. Parentage and relatedness analysis were conducted to track the genetic lineage of trees from each site. Our findings indicate that, even though adaptive SNPs seem to provide more insightful information than the genome-wide set, the optimal approach for evolutionary studies is a combination of both. Changes in adaptive genomic diversity and DNA methylation were observed between vigor classes, revealing the existence of a molecular basis behind the ongoing decline events in silver forests. Besides, trees’ relatives display a higher mixture of origins in coldspots, which could provide a temporary refuge for the species’ genetic diversity and adaptive potential. All in all, both genetic and epigenetic characteristics should be considered in order to comprehend how forest trees respond to climate stress to achieve adaptation to climate change.

How can biodiversity strategy and action plans incorporate genetic diversity and align with global commitments?

Abstract National, subnational, and supranational entities are creating biodiversity strategy and action plans (BSAPs) to develop concrete commitments and actions to curb biodiversity loss, meet international obligations, and achieve a society in harmony with nature. In light of policymakers’ increasing recognition of genetic diversity in species and ecosystem adaptation and resilience, this article provides an overview of how BSAPs can incorporate species’ genetic diversity. We focus on three areas: setting targets; committing to actions, policies, and programs; and monitoring and reporting. Drawing from 21 recent BSAPs, we provide examples of policies, knowledge, projects, capacity building, and more. We aim to enable and inspire specific and ambitious BSAPs and have put forward 10 key suggestions mapped to the policy cycle. Together, scientists and policymakers can translate high level commitments, such as the Convention on Biological Diversity’s Kunming–Montreal Global Biodiversity Framework, into concrete nationally relevant targets, actions and policies, and monitoring and reporting mechanisms.

Selection on synonymous codon usage in soybean (Glycine max) WRKY genes

The WRKY transcription factor gene family in soybean [Glycine max (L.) Merr.] (GmWRKY) is critical for the plant’s development and stress responses. This study examines the evolutionary dynamics of the GmWRKY gene family, focusing on its synonymous codon usage bias (CUB) in a comprehensive set of 179 coding sequences. CUB was analyzed using various indices, revealing a preference for A/T-ending codons and relatively low codon bias. Codon adaptation index (CAI) analysis suggested that these genes are optimized for efficient translation despite relatively low bias, reflecting a balance between codon diversity and translation efficiency. Neutrality and NC plots indicated that selective forces dominate over mutational forces in shaping codon usage, while selection signature analysis showed purifying selection being prevalent across the gene family. However, episodic positive selection was also detected in certain clades, highlighting potential adaptive diversification in response to environmental stress. Additionally, promoter binding site analysis uncovered correlations between codon usage and transcriptional regulation, indicating a context-dependent relationship between CUB and gene expression. Phylogenetic analysis identified 11 well-supported clades in the modern GmWRKY gene family and ancestral sequence reconstruction revealed more relaxed codon preferences and reduced selection constraints in modern GmWRKY genes, potentially linked to neofunctionalization and adaptation to environmental changes. These findings provide a framework for optimizing gene expression in transgenic soybean crops with resilience. Further functional validation of positively selected genes is recommended to elucidate their role in stress responses.

Genomic Data Support the Revision of Provenance Regions Delimitation for Scots Pine.

Scots pine is a crucial component of ecosystems in Europe and Asia and a major utility species that comprises more than 60% of total forest production in Poland. Despite its importance, the genetic relationships between key conservation and the commercial value of Scots pine ecotypes in Poland remain unclear. To address this problem, we analyzed 27 populations (841 trees) of the most valuable Polish Scots pine ecotypes, including the oldest natural stands in all 24 regions of provenance established for the species in the country. By examining maternally inherited mitochondrial markers, nuclear microsatellite loci, and thousands of SNP markers from a genotyping array, we evaluated the genetic structure between and within them. These multilevel genomic data revealed high genetic similarity and a homogeneous structure in most populations, suggesting a common historical origin and admixture of populations after the postglacial recolonization of Central Europe. This research presents novel data on existing genomic resources among local ecotypes defined within strictly managed Polish regions of provenance, challenging their validity. Formal tests of the progeny of seed stands are needed to check whether the diversity in adaptation and quantitative traits still supports the delineation of provenance regions. In parallel, the health status of selected populations and the viability of seeds from these regions should be monitored to detect early-stage symptoms of their environmental stress. It seems reasonable that periodic shortages of forest reproductive material (FRM) in a given region of provenance could be supplemented with the one from other regions that match their climatic envelope. Together, our results have important implications for the management of native Scots pine stands, particularly elite breeding populations, as they contribute to the discussion of the boundaries of provenance regions and the transfers of FRM that face increasing climate change.

Genomics-Informed Range Predictions Under Global Warming Reveal Reduced Adaptive Diversity Whilst Buffering Range Shifts for a Marine Snail.

Understanding the genetic basis of local adaptation in thermal performance is useful for predicting species distribution shifts under anthropogenic climate change. Many species are distributed across multiple biogeographic regions, and the uniquely adapted populations in each region may respond to future ocean warming with distinct distribution changes. In the present study, we investigated phylogeographic patterns, thermal sensitivity, and genetic differentiation in the intertidal snail Littorina brevicula along China's coast. Whole-genome sequencing results based on a newly assembled chromosome-level genome revealed two genetic lineages, with a north-south divergence that is linked to the thermal environment. Within each lineage, individuals could be further subdivided into genetic subgroups that differ at key genomic loci underpinning differences in upper heat tolerance. Heat stress drives adaptive divergence across multiple levels of organization, from the individual to the biogeographic level. Taking into account genetic diversity associated with variation in heat tolerance, a physiological species distribution model (pSDM) was applied to predict the distributions of the different genetic subgroups in response to climate change. Both northern and southern lineages were predicted to experience declines in habitat suitability under a 4°C future warming scenario, and that a genotypic subset of snails from the southern lineage may even be driven to extinction. These findings illustrate that even when a species' range is maintained, it can nonetheless experience a significant decrease in adaptive diversity as a result of climate change. The integrated approach presented here, which considered both physiological and adaptive genetic variation at the level of individuals within a biogeographical context, provided new insights into how marine species can respond to global warming.

Diversity of Transcriptional Regulatory Adaptation in E. coli.

The transcriptional regulatory network (TRN) in bacteria is thought to rapidly evolve in response to selection pressures, modulating transcription factor (TF) activities and interactions. In order to probe the limits and mechanisms surrounding the short-term adaptability of the TRN, we generated, evolved, and characterized knockout (KO) strains in Escherichia coli for 11 regulators selected based on measured growth impact on glucose minimal media. All but one knockout strain (Δlrp) were able to recover growth and did so requiring few convergent mutations. We found that the TF knockout adaptations could be divided into four categories: (i) Strains (ΔargR, ΔbasR, Δlon, ΔzntR, and Δzur) that recovered growth without any regulator-specific adaptations, likely due to minimal activity of the regulator on the growth condition, (ii) Strains (ΔcytR, ΔmlrA, and ΔybaO) that recovered growth without TF-specific mutations but with differential expression of regulators with overlapping regulons to the KO'ed TF, (iii) Strains (Δcrp and Δfur) that recovered growth using convergent mutations within their regulatory networks, including regulated promoters and connected regulators, and (iv) Strains (Δlrp) that were unable to fully recover growth, seemingly due to the broad connectivity of the TF within the TRN. Analyzing growth capabilities in evolved and unevolved strains indicated that growth adaptation can restore fitness to diverse substrates often despite a lack of TF-specific mutations. This work reveals the breadth of TRN adaptive mechanisms and suggests these mechanisms can be anticipated based on the network and functional context of the perturbed TFs.

Stress physiology of Moringa oleifera under tropospheric ozone enrichment: An ecotype-specific investigation into growth, nonstructural carbohydrates, and polyphenols.

Ozone (O3) is an oxidative pollutant that significantly threatens plant development and ecological dynamics. The present study explores the impact of O3 on Moringa (Moringa oleifera) ecotypes when exposed to ambient and elevated O3 levels. Elevated O3 concentrations resulted in significant reductions in total biomass for all ecotypes. Photosynthetic parameters, including stomatal conductance (gsto), CO2 assimilation (Pn), and carboxylation efficiency (K), decreased under elevated O3 in some ecotypes, indicating a detrimental effect on carbon assimilation. Nonstructural carbohydrate (NSC) levels in roots varied among ecotypes, with significant reductions in starch content observed under elevated O3, suggesting a potential shift towards soluble sugar accumulation and reallocation for antioxidant defense. Secondary metabolite analysis revealed increased polyphenol production, particularly quercetin derivatives, under elevated O3 in specific ecotypes, highlighting their role in mitigating oxidative stress. Interestingly, the glucosinolate content also varied, with some ecotypes exhibiting increased levels, suggesting a complex regulatory mechanism in response to O3 exposure. The study underscores the intrinsic variability among Moringa ecotypes in response to O3 stress, emphasizing the importance of genetic diversity for adaptation. The findings indicate that Moringa's metabolic plasticity, including shifts in NSC and SM production, plays a crucial role in its defense mechanisms against O3-induced oxidative stress. These insights are vital for optimizing the cultivation and utilization of Moringa in diverse environmental conditions, particularly in regions with elevated O3 levels.

The Mysterious World of Non-Canonical Caps - What We Know and Why We Need New Sequencing Techniques.

It was long believed that viral and eukaryotic mRNA molecules are capped at their 5' end solely by the N7-methylguanosine cap, which regulates various aspects of the RNA life cycle, from its biogenesis to its decay. However, the recent discovery of a variety of non-canonical RNA caps derived from metabolites and cofactors - such as NAD, FAD, CoA, UDP-glucose, UDP-N-acetylglucosamine, and dinucleoside polyphosphates - has expanded the known repertoire of RNA modifications. These non-canonical caps are found across all domains of life and can impact multiple aspects of RNA metabolism, including stability, translation initiation, and cellular stress responses. The study of these modifications has been facilitated by sophisticated methodologies such as liquid chromatography-mass spectrometry, which have unveiled their presence in both prokaryotic and eukaryotic organisms. The identification of these novel RNA caps highlights the need for advanced sequencing techniques to characterize the specific RNA types bearing these modifications and understand their roles in cellular processes. Unravelling the biological role of non-canonical RNA caps will provide insights into their contributions to gene expression, cellular adaptation, and evolutionary diversity. This review emphasizes the importance of these technological advancements in uncovering the complete spectrum of RNA modifications and their implications for living systems.

Seasonal stability of the rumen microbiome contributes to the adaptation patterns to extreme environmental conditions in grazing yak and cattle

BackgroundThe rumen microbiome plays an essential role in maintaining ruminants’ growth and performance even under extreme environmental conditions, however, which factors influence rumen microbiome stability when ruminants are reared in such habitats throughout the year is unclear. Hence, the rumen microbiome of yak (less domesticated) and cattle (domesticated) reared on the Qinghai-Tibetan Plateau through the year were assessed to evaluate temporal changes in their composition, function, and stability.ResultsRumen fermentation characteristics and pH significantly shifted across seasons in both cattle and yak, but the patterns differed between the two ruminant species. Ruminal enzyme activity varied with season, and production of xylanase and cellulase was greater in yak compared to cattle in both fall and winter. The rumen bacterial community varied with season in both yak and cattle, with higher alpha diversity and similarity (beta diversity) in yak than cattle. The diversity indices of eukaryotic community did not change with season in both ruminant species, but higher similarity was observed in yak. In addition, the similarity of rumen microbiome functional community was higher in yak than cattle across seasons. Moreover, yak rumen microbiome encoded more genes (GH2 and GH3) related to cellulose and hemicellulose degradation compared to cattle, and a new enzyme family (GH160) gene involved in oligosaccharides was uniquely detected in yak rumen. The season affected microbiome attenuation and buffering values (stability), with higher buffering value in yak rumen microbiome than cattle. Positive correlations between antimicrobial resistance gene (dfrF) and CAZyme family (GH113) and microbiome stability were identified in yak, but such relationship was negatively correlated in cattle.ConclusionsThe findings of the potential of cellulose degradation, the relationship between rumen microbial stability and the abundance of functional genes varied differently across seasons and between yak and cattle provide insight into the mechanisms that may underpin their divergent adaptation patterns to the harsh climate of the Qinghai-Tibetan Plateau. These results lay a solid foundation for developing strategies to maintain and improve rumen microbiome stability and dig out the potential candidates for manufacturing lignocellulolytic enzymes in the yak rumen to enhance ruminants’ performance under extreme environmental conditions.