The aim of this study was to describe the morphology of the tongue of the okapi, and to compare the results with other ruminants including browsers, intermediates and grazers. The material was collected post-mortem from two animals from a Zoological Garden. The structure of the okapi tongue, focusing of the shape of the tongue, lingual surface, its papillae and lingual glands, was examined using gross morphology, light and polarized microscopy, and by scanning electron microscopy. The okapi tongue was characterized by dark pigmentation on the lingual dorsum (except lingual torus) and on the whole ventral surface. Two types of filiform papillae were observed, with additional, even 6-8 projections at their base. The round fungiform papillae were present at a higher density, up to 16/cm2, on the ventro-lateral area of the lingual apex. Round and elongate vallate papillae were arranged in two parallel lines between the body and root of the tongue. Numerous taste buds were detected within the epithelium of their vallum, while fungiform papillae had sparse taste buds. A lack of foliate papillae was noted. Very small conical papillae, some lenticular in shape, were present on the lingual torus. Thick collagen type I fibers were dominant over collagen type III fibers in the connective tissue of the lingual papillae. The mucous acini units were dominant among lingual glands, indicating that the secretion of okapi lingual glands was mostly mucous. In many aspects, the tongue of okapi resembles the tongue of other ruminants. The specific lingual shape and lingual surface, together with the lingual glands, support the processing of plant food, such as young and soft leaves. Although okapi tongue is characterized by smaller conical papillae compared to other ruminants, its high number of vallate papillae is similar that found in other browsers, intermediate and grazers. Thus the number of gustatory papillae rather indicates that this feature is not related to the type of feeding.

• Klíčová slova
• Okapia johnstoni, adaptation, histochemistry, histology, lingual glands, morphology, oral cavity, scanning electron microscopy, selective browser, type I collagen fiber, type III collagen fiber,
• MeSH
• Artiodactyla anatomie a histologie   MeSH
• chuťové pohárky * ultrastruktura   anatomie a histologie   MeSH
• fyziologická adaptace MeSH
• jazyk * ultrastruktura   anatomie a histologie   MeSH
• mikroskopie elektronová rastrovací MeSH
• žirafy anatomie a histologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The identification of genes involved in salinity tolerance has primarily focused on model plants and crops. However, plants naturally adapted to highly saline environments offer valuable insights into tolerance to extreme salinity. Salicornia plants grow in coastal salt marshes, stimulated by NaCl. To understand this tolerance, we generated genome sequences of two Salicornia species and analyzed the transcriptomic and proteomic responses of Salicornia bigelovii to NaCl. Subcellular membrane proteomes reveal that SbiSOS1, a homolog of the well-known SALT-OVERLY-SENSITIVE 1 (SOS1) protein, appears to localize to the tonoplast, consistent with subcellular localization assays in tobacco. This neo-localized protein can pump Na+ into the vacuole, preventing toxicity in the cytosol. We further identify 11 proteins of interest, of which SbiSALTY, substantially improves yeast growth on saline media. Structural characterization using NMR identified it as an intrinsically disordered protein, localizing to the endoplasmic reticulum in planta, where it can interact with ribosomes and RNA, stabilizing or protecting them during salt stress.

• MeSH
• Chenopodiaceae * metabolismus   genetika   účinky léků   MeSH
• chlorid sodný farmakologie   metabolismus   MeSH
• endoplazmatické retikulum metabolismus   MeSH
• proteomika MeSH
• regulace genové exprese u rostlin účinky léků   MeSH
• rostlinné proteiny * metabolismus   genetika   MeSH
• salinita MeSH
• solný stres MeSH
• tabák metabolismus   genetika   účinky léků   MeSH
• tolerance k soli * genetika   MeSH
• transkriptom MeSH
• vakuoly metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH

While endophytic fungi offer promising avenues for bolstering plant resilience against abiotic stressors, the molecular mechanisms behind this biofortification remain largely unknown. This study employed a multifaceted approach, combining plant physiology, proteomic, metabolomic, and targeted hormonal analyses to illuminate the early response of Brassica napus to Acremonium alternatum during the nascent stages of their interaction. Notably, under optimal growth conditions, the initial reaction to fungus was relatively subtle, with no visible alterations in plant phenotype and only minor impacts on the proteome and metabolome. Interestingly, the identified proteins associated with the Acremonium response included TUDOR 1, Annexin D4, and a plastidic K+ efflux antiporter, hinting at potential processes that could counter abiotic stressors, particularly salt stress. Subsequent experiments validated this hypothesis, showcasing significantly enhanced growth in Acremonium-inoculated plants under salt stress. Molecular analyses revealed a profound impact on the plant's proteome, with over 50% of salt stress response proteins remaining unaffected in inoculated plants. Acremonium modulated ribosomal proteins, increased abundance of photosynthetic proteins, enhanced ROS metabolism, accumulation of V-ATPase, altered abundances of various metabolic enzymes, and possibly promoted abscisic acid signaling. Subsequent analyses validated the accumulation of this hormone and its enhanced signaling. Collectively, these findings indicate that Acremonium promotes salt tolerance by orchestrating abscisic acid signaling, priming the plant's antioxidant system, as evidenced by the accumulation of ROS-scavenging metabolites and alterations in ROS metabolism, leading to lowered ROS levels and enhanced photosynthesis. Additionally, it modulates ion sequestration through V-ATPase accumulation, potentially contributing to the observed decrease in chloride content.

• MeSH
• Acremonium * metabolismus   fyziologie   MeSH
• Brassica napus mikrobiologie   metabolismus   fyziologie   účinky léků   MeSH
• fotosyntéza MeSH
• homeostáza * MeSH
• kyselina abscisová metabolismus   MeSH
• oxidace-redukce * MeSH
• regulátory růstu rostlin * metabolismus   MeSH
• rostlinné proteiny metabolismus   genetika   MeSH
• signální transdukce * MeSH
• solný stres fyziologie   MeSH
• tolerance k soli * fyziologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kyselina abscisová MeSH
• regulátory růstu rostlin * MeSH
• rostlinné proteiny MeSH

Assessing the association between temperature frequency and mortality can provide insights into human adaptation to local ambient temperatures. We collected daily time-series data on mortality and temperature from 757 locations in 47 countries/regions during 1979-2020. We used a two-stage time series design to assess the association between temperature frequency and all-cause mortality. The results were pooled at the national, regional, and global levels. We observed a consistent decrease in the risk of mortality as the normalized frequency of temperature increases across the globe. The average increase in mortality risk comparing the 10th to 100th percentile of normalized frequency was 13.03% (95% CI: 12.17-13.91), with substantial regional differences (from 4.56% in Australia and New Zealand to 33.06% in South Europe). The highest increase in mortality was observed for high-income countries (13.58%, 95% CI: 12.56-14.61), followed by lower-middle-income countries (12.34%, 95% CI: 9.27-15.51). This study observed a declining risk of mortality associated with higher temperature frequency. Our findings suggest that populations can adapt to their local climate with frequent exposure, with the adapting ability varying geographically due to differences in climatic and socioeconomic characteristics.

• Klíčová slova
• Adaptation, Climate change, Frequency, Mortality, Temperature,
• MeSH
• aklimatizace fyziologie   MeSH
• klimatické změny MeSH
• lidé MeSH
• mortalita * trendy   MeSH
• podnebí MeSH
• teplota MeSH
• vysoká teplota škodlivé účinky   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Austrálie MeSH
• Nový Zéland MeSH

One of the most vulnerable phases in the plant life cycle is sexual reproduction, which depends on effective pollen transfer, but also on the thermotolerance of pollen grains. Pollen thermotolerance is temperature-dependent and may be reduced by increasing temperature associated with global warming. A growing body of research has focused on the effect of increased temperature on pollen thermotolerance in crops to understand the possible impact of temperature extremes on yield. Yet, little is known about the effects of temperature on pollen thermotolerance of wild plant species. To fill this gap, we selected Lotus corniculatus s.l. (Fabaceae), a species common to many European habitats and conducted laboratory experiments to test its pollen thermotolerance in response to artificial increase in temperature. To test for possible local adaptation of pollen thermal tolerance, we compared data from six lowland (389-451 m a.s.l.) and six highland (841-1,030 m a.s.l.) populations. We observed pollen germination in vitro at 15 °C, 25 °C, 30 °C, and 40 °C. While lowland plants maintained a stable germination percentage across a broad temperature range (15-30 °C) and exhibited reduced germination only at extremely high temperatures (40 °C), highland plants experienced reduced germination even at 30 °C-temperatures commonly exceeded in lowlands during warm summers. This suggests that lowland populations of L. corniculatus may be locally adapted to higher temperature for pollen germination. On the other hand, pollen tube length decreased with increasing temperature in a similar way in lowland and highland plants. The overall average pollen germination percentage significantly differed between lowland and highland populations, with highland populations displaying higher germination percentage. On the other hand, the average pollen tube length was slightly smaller in highland populations. In conclusion, we found that pollen thermotolerance of L. corniculatus is reduced at high temperature and that the germination of pollen from plant populations growing at higher elevations is more sensitive to increased temperature, which suggests possible local adaptation of pollen thermotolerance.

• Klíčová slova
• Elevational gradient, Heat stress, Local adaptation, Plant reproduction, Pollen, Pollen viability, Pollination, Thermotolerance,
• MeSH
• aklimatizace fyziologie   MeSH
• fyziologická adaptace fyziologie   MeSH
• globální oteplování MeSH
• klíčení fyziologie   MeSH
• klimatické změny MeSH
• Lotus * fyziologie   růst a vývoj   MeSH
• nadmořská výška MeSH
• pyl * fyziologie   MeSH
• teplota MeSH
• termotolerance * fyziologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Crimean-Congo haemorrhagic fever orthonairovirus (CCHFV) is a negative-sense, single-stranded RNA virus with a segmented genome and the causative agent of a severe Crimean-Congo haemorrhagic fever (CCHF) disease. The virus is transmitted mainly by tick species in Hyalomma genus but other ticks such as representatives of genera Dermacentor and Rhipicephalus may also be involved in virus life cycle. To improve our understanding of CCHFV adaptation to its tick species, we compared nucleotide composition and codon usage patterns among the all CCHFV strains i) which sequences and other metadata as locality of collection and date of isolation are available in GenBank and ii) which were isolated from in-field collected tick species. These criteria fulfilled 70 sequences (24 coding for S, 23 for M, and 23 for L segment) of virus isolates originating from different representatives of Hyalomma and Rhipicephalus genera. Phylogenetic analyses confirmed that Hyalomma- and Rhipicephalus-originating CCHFV isolates belong to phylogenetically distinct CCHFV clades. Analyses of nucleotide composition among the Hyalomma- and Rhipicephalus-originating CCHFV isolates also showed significant differences, mainly in nucleotides located at the 3rd codon positions indicating changes in codon usage among these lineages. Analyses of codon adaptation index (CAI), effective number of codons (ENC), and other codon usage statistics revealed significant differences between Hyalomma- and Rhipicephalus-isolated CCHFV strains. Despite both sets of strains displayed a higher adaptation to use codons that are preferred by Hyalomma ticks than Rhipicephalus ticks, there were distinct codon usage preferences observed between the two tick species. These findings suggest that over the course of its long co-evolution with tick vectors, CCHFV has optimized its codon usage to efficiently utilize translational resources of Hyalomma species.

• MeSH
• fylogeneze * MeSH
• fyziologická adaptace genetika   MeSH
• hemoragická horečka krymská virologie   genetika   MeSH
• Ixodidae virologie   genetika   MeSH
• klíšťata virologie   genetika   MeSH
• virus krymsko-konžské hemoragické horečky * genetika   MeSH
• využití kodonu MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The emergence of bacterial species is rooted in their inherent potential for continuous evolution and adaptation to an ever-changing ecological landscape. The adaptive capacity of most species frequently resides within the repertoire of genes encoding the secreted proteome (SP), as it serves as a primary interface used to regulate survival/reproduction strategies. Here, by applying evolutionary genomics approaches to metagenomics data, we show that abundant freshwater bacteria exhibit biphasic adaptation states linked to the eco-evolutionary processes governing their genome sizes. While species with average to large genomes adhere to the dominant paradigm of evolution through niche adaptation by reducing the evolutionary pressure on their SPs (via the augmentation of functionally redundant genes that buffer mutational fitness loss) and increasing the phylogenetic distance of recombination events, most of the genome-reduced species exhibit a nonconforming state. In contrast, their SPs reflect a combination of low functional redundancy and high selection pressure, resulting in significantly higher levels of conservation and invariance. Our findings indicate that although niche adaptation is the principal mechanism driving speciation, freshwater genome-reduced bacteria often experience extended periods of adaptive stasis. Understanding the adaptive state of microbial species will lead to a better comprehension of their spatiotemporal dynamics, biogeography, and resilience to global change.

• MeSH
• Bacteria * genetika   klasifikace   MeSH
• délka genomu MeSH
• fylogeneze * MeSH
• fyziologická adaptace * genetika   MeSH
• genom bakteriální * MeSH
• metagenomika metody   MeSH
• molekulární evoluce MeSH
• proteom genetika   metabolismus   MeSH
• sladká voda * mikrobiologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• proteom MeSH

The ability to respond to varying environments is crucial for sessile organisms such as plants. The amphibious plant Rorippa aquatica exhibits a striking type of phenotypic plasticity known as heterophylly, a phenomenon in which leaf form is altered in response to environmental factors. However, the underlying molecular mechanisms of heterophylly are yet to be fully understood. To uncover the genetic basis and analyze the evolutionary processes driving heterophylly in R. aquatica, we assembled the chromosome-level genome of the species. Comparative chromosome painting and chromosomal genomics revealed that allopolyploidization and subsequent post-polyploid descending dysploidy occurred during the speciation of R. aquatica. Based on the obtained genomic data, the transcriptome analyses revealed that ethylene signaling plays a central role in regulating heterophylly under submerged conditions, with blue light signaling acting as an attenuator of ethylene signal. The assembled R. aquatica reference genome provides insights into the molecular mechanisms and evolution of heterophylly.

• MeSH
• chromozomy MeSH
• ethyleny MeSH
• fyziologická adaptace MeSH
• listy rostlin genetika   MeSH
• Rorippa * genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ethyleny MeSH

Many ectothermic organisms counter harsh abiotic conditions by seeking refuge in underground retreats. Variations in soil hydrothermal properties within these retreats may impact their energy budget, survival and population dynamics. This makes retreat site choice a critical yet understudied component of their strategies for coping with climate change. We used a mechanistic modelling approach to explore the implications of behavioural adjustments and seasonal acclimation of metabolic rate on retreat depth and the energy budget of ectotherms, considering both current and future climate conditions. We used a temperate amphibian, the alpine newt (Ichthyosaura alpestris), as a model species. Our simulations predict an interactive influence of different thermo- and hydroregulatory strategies on the vertical positioning of individuals in underground refuges. The adoption of a particular strategy largely determines the impact of climate change on retreat site choice. Additionally, we found that, given the behavioural thermoregulation/hydroregulation and metabolic acclimation patterns considered, behaviour within the retreat has a greater impact on ectotherm energetics than acclimation of metabolic rate under different climate change scenarios. We conclude that further empirical research aimed at determining ectotherm behavioural strategies during both surface activity and inactivity is needed to understand their population dynamics and species viability under climate change.

• Klíčová slova
• energy budget, hydroregulation, mechanistic niche modelling, retreat site choice, thermoregulation,
• MeSH
• aklimatizace * MeSH
• chování zvířat fyziologie   MeSH
• klimatické změny * MeSH
• lidé MeSH
• půda MeSH
• teplota MeSH
• termoregulace MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• půda MeSH

Terrestrial ectotherms react to acute changes in environmental temperatures by adjusting their behaviour. Evaluating the adaptive potential of these behavioural adjustments requires information on their repeatability and plasticity. We examined behavioural response (exploration) to acute temperature change in two amphibian taxa, alpine (Ichthyosaura alpestris) and smooth (Lissotriton vulgaris) newts. These responses were investigated at both population and individual levels under multiple thermal contexts (dimensions), represented by the direction and range of changing temperature and rearing thermal regimes. Population-level analyses showed species-specific, non-additive effects of direction and range of temperature change on acute thermal reaction norms for exploration, but explained only a low amount (7-23%) of total variation in exploration. In contrast, within- and among-individual variation in acute thermal reaction norm parameters explained 42-50% of total variation in the examined trait. Although immediate thermal responses varied among individuals (repeatability = 0.07 to 0.53), they were largely shaped by environmental contexts during repeated trials. We conclude that these amphibians respond to acute temperature change through individual plasticity of behavioural traits. A repeated-measures approach under multiple thermal contexts will be needed to identify the selective and plastic potential of behavioural responses used by juvenile newts and perhaps other ectotherm taxa to cope with rapidly changing environmental temperatures.

• Klíčová slova
• Behavioural plasticity, Environmental change, Personality, Repeatability, Thermal performance curve,
• MeSH
• lidé MeSH
• pátrací chování * MeSH
• Salamandridae fyziologie   MeSH
• tělesná teplota * MeSH
• teplota MeSH
• termoregulace fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH