RESUMO
Camouflage is a classic example of a trait wherein animals respond to natural selection to avoid predation or attract prey. This unique phenomenon has attracted significant recent attention and the rapid development of integrative research methods is facilitating advances in our understanding of the in-depth genetic mechanisms of camouflage. In this review article, we revisit camouflage definitions and strategies and then we examine the underlying mechanisms of the two most common forms of camouflage, crypsis and masquerade, that have recently been elucidated using multiple approaches. We also discuss unresolved questions related to camouflage. Ultimately, we highlight the implications of camouflage for informing various key issues in ecology and evolution.
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Evolução Biológica , Mimetismo Biológico , Seleção Genética , Animais , Mimetismo Biológico/genética , Seleção Genética/genética , Comportamento Predatório , Fenótipo , Pigmentação/genéticaRESUMO
Reintroduction programs seek to restore degraded populations and reverse biodiversity loss. To examine the hypothesis that gut symbionts could be used as an indicator of reintroduction success, we performed intensive metagenomic monitoring over 10 years to characterize the ecological succession and adaptive evolution of the gut symbionts of captive giant pandas reintroduced to the wild. We collected 63 fecal samples from 3 reintroduced individuals and 22 from 9 wild individuals and used 96 publicly available samples from another 3 captive individuals. By microbial composition analysis, we identified 3 community clusters of the gut microbiome (here termed enterotypes) with interenterotype succession that was closely related to the reintroduction process. Each of the 3 enterotypes was identified based on significant variation in the levels of 1 of 3 genera: Clostridium, Pseudomonas, and Escherichia. The enterotype of captive pandas was Escherichia. This enterotype was gradually replaced by the Clostridium enterotype during the wild-training process, which in turn was replaced by the Pseudomonas enterotype that resembled the enterotype of wild pandas, an indicator of conversion to wildness and a successful reintroduction. We also isolated 1 strain of Pseudomonas protegens from the wild enterotype, a previously reported free-living microbe, and found that its within-host evolution contributed to host dietary adaptation in the wild. Monitoring gut microbial structure provides a novel, noninvasive tool that can be used as an indicator of successful reintroduction of a captive individual to the wild.
Microbiomas intestinales como indicadores clave de monitoreo para la reintroducción de animales cautivos Resumen Los programas de reintroducción buscan restaurar las poblaciones degradadas y revertir la pérdida de la biodiversidad. Realizamos un monitoreo metagenómico intensivo durante más de diez años para caracterizar la sucesión ecológica y la evolución adaptativa de los simbiontes intestinales de pandas reintroducidos en la naturaleza y así comprobar la hipótesis de que estos simbiontes pueden usarse como indicadores de una reintroducción exitosa. Recolectamos 63 muestras fecales de tres individuos reintroducidos y 22 de nueve individuos silvestres y usamos 96 muestras disponibles al público de otros tres individuos cautivos. Mediante el análisis de la composición microbiana identificamos tres grupos comunitarios del microbioma intestinal (denominados como enterotipos) con una sucesión entre enterotipos relacionada cercanamente al proceso de reintroducción. Identificamos cada uno de los tres enterotipos con base en la variación significativa en los niveles de uno de los tres géneros: Clostridium, Pseudomonas, y Escherichia. El enterotipo de los pandas cautivos fue Escherichia. A este enterotipo lo reemplazó gradualmente el enterotipo de Clostridium durante el proceso de adaptación a la naturaleza, y a su vez fue reemplazado por el enterotipo de Pseudomonas similar al de los pandas silvestres, un indicador de la conversión a la vida silvestre y de una reintroducción exitosa. También aislamos una cepa de Pseudomonas protegens del enterotipo silvestre, un microbio reportado previamente como de vida libre, y descubrimos que su evolución dentro del hospedero contribuyó a que este se adaptara a la naturaleza de la dieta. El monitoreo de la estructura microbiana intestinal proporciona una herramienta novedosa y no invasiva que puede usarse como indicador del éxito de la reintroducción de un individuo cautivo a la naturaleza.
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Microbioma Gastrointestinal , Ursidae , Humanos , Animais , Conservação dos Recursos Naturais , Biodiversidade , Fezes , DietaRESUMO
Incorrect species delimitation will lead to inappropriate conservation decisions, especially for threatened species. The takin (Budorcas taxicolor) is a large artiodactyl endemic to the Himalayan-Hengduan-Qinling Mountains and is well known for its threatened status and peculiar appearance. However, the speciation, intraspecies taxonomy, evolutionary history, and adaptive evolution of this species still remain unclear, which greatly hampers its scientific conservation. Here, we de novo assembled a high-quality chromosome-level genome of takin and resequenced the genomes of 75 wild takins. Phylogenomics revealed that takin was positioned at the root of Caprinae. Population genomics based on the autosome, X chromosome, and Y chromosome SNPs and mitochondrial genomes consistently revealed the existence of two phylogenetic species and recent speciation in takins: the Himalayan takin (B. taxicolor) and the Chinese takin (B. tibetana), with the support of morphological evidence. Two genetically divergent subspecies were identified in both takin species, rejecting three previously proposed taxonomical viewpoints. Furthermore, their distribution boundaries were determined, suggesting that large rivers play important roles in shaping the genetic partition. Compared with the other subspecies, the Qinling subspecies presented the lowest genomic diversity, higher linkage disequilibrium, inbreeding, and genetic load, thus is in urgent need of genetic management and protection. Moreover, coat color gene (PMEL) variation may be responsible for the adaptive coat color difference between the two species following Gloger's rule. Our findings provide novel insights into the recent speciation, local adaptation, scientific conservation of takins, and biogeography of the Himalaya-Hengduan biodiversity hotspot.
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Genoma Mitocondrial , Ruminantes , Animais , Espécies em Perigo de Extinção , Especiação Genética , Genômica , Filogenia , Ruminantes/genéticaRESUMO
Attraction to feces in wild mammalian species is extremely rare. Here we introduce the horse manure rolling (HMR) behavior of wild giant pandas (Ailuropoda melanoleuca). Pandas not only frequently sniffed and wallowed in fresh horse manure, but also actively rubbed the fecal matter all over their bodies. The frequency of HMR events was highly correlated with an ambient temperature lower than 15 °C. BCP/BCPO (beta-caryophyllene/caryophyllene oxide) in fresh horse manure was found to drive HMR behavior and attenuated the cold sensitivity of mice by directly targeting and inhibiting transient receptor potential melastatin 8 (TRPM8), an archetypical cold-activated ion channel of mammals. Therefore, horse manure containing BCP/BCPO likely bestows the wild giant pandas with cold tolerance at low ambient temperatures. Together, our study described an unusual behavior, identified BCP/BCPO as chemical inhibitors of TRPM8 ion channel, and provided a plausible chemistry-auxiliary mechanism, in which animals might actively seek and utilize potential chemical resources from their habitat for temperature acclimatization.
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Comportamento Animal , Esterco , Canais de Cátion TRPM/genética , Ursidae , Animais , Feminino , Células HEK293 , Cavalos , Humanos , Masculino , Esterco/análise , Camundongos Endogâmicos C57BL , Filogenia , Sesquiterpenos Policíclicos/análise , Sesquiterpenos Policíclicos/farmacologia , Pirimidinonas/farmacologia , Ratos Wistar , Canais de Cátion TRPM/metabolismo , TemperaturaRESUMO
Antagonistic coevolution between host and parasite drives species evolution. However, most of the studies only focus on parasitism adaptation and do not explore the coevolution mechanisms from the perspective of both host and parasite. Here, through the de novo sequencing and assembly of the genomes of giant panda roundworm, red panda roundworm, and lion roundworm parasitic on tiger, we investigated the genomic mechanisms of coevolution between nonmodel mammals and their parasitic roundworms and those of roundworm parasitism in general. The genome-wide phylogeny revealed that these parasitic roundworms have not phylogenetically coevolved with their hosts. The CTSZ and prolyl 4-hydroxylase subunit beta (P4HB) immunoregulatory proteins played a central role in protein interaction between mammals and parasitic roundworms. The gene tree comparison identified that seven pairs of interactive proteins had consistent phylogenetic topology, suggesting their coevolution during host-parasite interaction. These coevolutionary proteins were particularly relevant to immune response. In addition, we found that the roundworms of both pandas exhibited higher proportions of metallopeptidase genes, and some positively selected genes were highly related to their larvae's fast development. Our findings provide novel insights into the genetic mechanisms of coevolution between nonmodel mammals and parasites and offer the valuable genomic resources for scientific ascariasis prevention in both pandas.
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Ascaridoidea/genética , Coevolução Biológica , Genoma Helmíntico , Interações Hospedeiro-Parasita/genética , Tigres/parasitologia , Ursidae/parasitologia , Animais , Filogenia , Mapas de Interação de Proteínas , Seleção Genética , Tigres/genética , Tigres/metabolismo , Ursidae/genética , Ursidae/metabolismoRESUMO
Coccidiosis, caused by different species of Eimeria parasites, is an economically important disease of poultry and livestock worldwide. Here we report previously unknown alterations in the gut microbes and metabolism of BALB/c mice infected with Eimeria falciformis Specifically, we observed a significant shift in the abundance of cecal bacteria and disrupted metabolism in parasitized animals. The relative abundances of Lachnospiraceae bacterium NK4A136, Ruminiclostridium, Alistipes, and Lactobacillus declined in response to E. falciformis infection, whereas Escherichia, Shigella, Helicobacter, Klebsiella, and Bacteroides were increased. Carbohydrate and amino acid metabolites in the serum samples of infected mice were significantly altered compared to naïve controls. Levels of amino acids, including asparagine, histidine, l-cysteine, tryptophan, lysine, glycine, serine, alanine, proline, ornithine, methionine, and valine, decreased on day 7 postinfection before returning to baseline on day 14. In addition, increased levels of indolelactate and mannitol and a reduced amount of oxalic acid indicated impaired carbon metabolism upon parasitic infection. These data demonstrate that intestinal coccidial infection perturbs the microbiota and disrupts carbon and nitrogen metabolism.
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Coccidiose/fisiopatologia , Eimeria/patogenicidade , Microbioma Gastrointestinal/fisiologia , Interações Hospedeiro-Parasita/fisiologia , Redes e Vias Metabólicas/fisiologia , Animais , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Diarrhea remains one of the leading causes of morbidity and mortality globally, with enterotoxigenic Escherichia coli (ETEC) constituting a major causative pathogen. The development of alternative treatments for diarrhea that do not involve chemotherapeutic drugs or result in antibiotic resistance is critical. Considering that lysozyme is a naturally occurring antimicrobial peptide, in a previous study we developed a transgenic pig line that expresses recombinant human lysozyme (hLZ) in its milk. In the present study, we examined the protective effects of the consumption of this milk against ETEC infection in neonatal piglets. We found that consuming hLZ milk facilitated faster recovery from infection and decreased mortality and morbidity following an ETEC oral inoculation or infection acquired by contact-exposure. The protective effect of hLZ was associated with the enrichment of intestinal bacteria that improve gut health, such as Lactobacillus, and the enhancement of the mucosal IgA response to the ETEC-induced diarrhea. Our study revealed potential protective mechanisms underlying the antimicrobial activity of human lysozyme, validating the use of lysozyme as an effective preventive measure for diarrhea.
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Antibacterianos/farmacologia , Diarreia/prevenção & controle , Infecções por Escherichia coli/veterinária , Enteropatias/veterinária , Leite/microbiologia , Muramidase/farmacologia , Doenças dos Suínos/prevenção & controle , Animais , Animais Geneticamente Modificados , Animais Recém-Nascidos , Antibacterianos/administração & dosagem , Diarreia/microbiologia , Diarreia/veterinária , Escherichia coli Enterotoxigênica/fisiologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle , Feminino , Enteropatias/microbiologia , Enteropatias/prevenção & controle , Muramidase/administração & dosagem , Suínos , Doenças dos Suínos/microbiologiaRESUMO
Molecular identification of Eimeria parasites infecting poultry and livestock has been commonly used for more than 20 years. An important step of the molecular identification technique is the rupturing of the oocyst wall for DNA extraction. Previously, DNA extraction methods included pre-treatment with sodium hypochlorite and osmotic shock with saturated salt solution. Here, we present a modification of this technique for a more sensitive and efficient identification of Eimeria spp. in field samples. The disruption extent of the oocyst walls, yield of DNA extraction, and identification of species-specific DNA sequences by PCR were used to evaluate this optimized method. Incubation of oocysts in sodium hypochlorite for 1.5 h at 4 °C followed by treatment with a saturated salt solution for 1 h at 55 °C broke up the walls of most Eimeria tenella oocysts, as well as other coccidian species of chicken and rabbit, such as Eimeria intestinalis and even Cryptosporidium cuniculus. Notably, polymerase chain reaction (PCR) amplification of the intervening transcribed sequence 1 (ITS-1) was successfully performed with genomic DNA extracted from just 50 oocysts using this optimized method. Our findings will greatly promote the development of molecular diagnosis methods of coccidiosis and simplify coccidian species identification and categorization as well as infection prevalence, providing a significant advancement in the development of techniques for coccidiosis control and prevention.
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Coccídios/classificação , DNA de Protozoário/isolamento & purificação , Animais , Galinhas/parasitologia , Coccídios/genética , Coccídios/isolamento & purificação , Coccidiose/parasitologia , Coccidiose/veterinária , Cryptosporidium/classificação , Cryptosporidium/genética , Eimeria/classificação , Eimeria/genética , Oocistos , Reação em Cadeia da Polimerase/métodos , Doenças das Aves Domésticas/parasitologia , Coelhos , Especificidade da EspécieRESUMO
The infection by Limnodrilus hoffmeisteri Claparède, 1862 (Oligochaeta: Tubificinae) in humans is relatively uncommon. The present report is to describe an incidental human infection with oligochaetes in the nasal cavity of a Chinese man, a 25-year-old man residing in Zhangjiakou city, Hebei province, China presenting with nose bleed, severe itching, continuous sneezing, and rhinorrhea. A lot of oligochaete worms were found in the nasal discharge of the patient. The detected worms were identified as Limnodrilus hoffmeisteri (Annelida: Oligochaeta) based on morphological and molecular characteristics. This incidental L. hoffmeisteri nasal infection is the first case in China and indicates that oligochaete worms can be encountered in humans.
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Cavidade Nasal/parasitologia , Oligoquetos/crescimento & desenvolvimento , Doenças Parasitárias/diagnóstico , Doenças Parasitárias/patologia , Adulto , Animais , China , Análise por Conglomerados , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Humanos , Masculino , Microscopia , Oligoquetos/anatomia & histologia , Oligoquetos/classificação , Oligoquetos/genética , Doenças Parasitárias/parasitologia , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNARESUMO
BACKGROUND: To explore the efficacy of tranexamic acid (TXA) on reducing hidden blood loss (HBL) in total knee arthroplasty (TKA) by conducting a comparative study and meta-analysis. MATERIAL/METHODS: A total of 108 patients underwent TKA was equally distributed to experimental and control groups. The only difference between two groups was the administrations of 15 mg of TXA mixed in 100 mL normal saline for experimental group and 100 mL of normal saline for control group. The volumes of blood loss, red blood loss (RBL) were recorded, calculated and analyzed. Stata 12.0 software was applied for data analysis. RESULTS: The intraoperative and postoperative blood loss volume in experimental group were remarkably reduced compared with those in control group (intraoperative: 105.1±12.1 mL vs. 185.5±20.3 mL, P<0.001; postoperative: 220.7±16.8 mL vs. 290.5±22.4 mL, P<0.001). Accordingly, the control group had significantly higher transfusion rate than experimental group (3.7% vs.25.9%, P=0.001). Our results also found that both the measured and hidden RBL were obviously reduced in experimental group compared with control group (measured RBL: 96.9±11.8 mL vs. 135.2±13.5 mL, P<0.001; hidden RBL: 170.8±37.2 mL vs. 364.2±41.5 mL, P<0.001). Furthermore, meta-analysis confirmed that TXA can notably decrease HBL (SMD=2.68, 95%CI=1.55~3.80, P<0.001). CONCLUSIONS: TXA can significantly reduce the intraoperative and postoperative blood loss and HBL, therefore decreasing the transfusion need in TKA.
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Artroplastia do Joelho/efeitos adversos , Perda Sanguínea Cirúrgica/prevenção & controle , Metanálise como Assunto , Ácido Tranexâmico/uso terapêutico , Idoso , Coagulação Sanguínea/efeitos dos fármacos , Transfusão de Sangue , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Hematócrito , Hemoglobinas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Tranexâmico/farmacologiaRESUMO
Sirenians exhibit unique aquatic adaptations, showcasing both convergent adaptive features shared with cetaceans and unique characteristics such as cold sensitivity and dense bones. Here, we report a chromosome-level genome of the African manatee (Trichechus senegalensis) with high continuity, completeness, and accuracy. We found that genes associated with osteopetrosis have undergone positive selection (CSF1R and LRRK1) or pseudogenized (FAM111A and IGSF23) in the African manatee, potentially contributing to the dense bone formation. The loss of KCNK18 may have increased their sensitivity to cold water temperatures. Moreover, we identified convergent evolutionary signatures in 392 genes among fully aquatic mammals, primarily enriched in skin or skeletal system development and circadian rhythm, which contributed to the transition from terrestrial to fully aquatic lifestyles. The African manatee currently possesses a small effective population size and low genome-wide heterozygosity. Overall, our study provides genetic resources for understanding the evolutionary characteristics and conservation efforts of this species.
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The Chinese pangolin (Manis pentadactyla, MP) has been extensively exploited and is now on the brink of extinction, but its population structure, evolutionary history, and adaptive potential are unclear. Here, we analyzed 94 genomes from three subspecies of the Chinese pangolin and identified three distinct genetic clusters (MPA, MPB, and MPC), with MPB further divided into MPB1 and MPB2 subpopulations. The divergence of these populations was driven by past climate change. For MPB2 and MPC, recent human activities have caused dramatic population decline and small population size as well as increased inbreeding, but not decrease in genomic variation and increase in genetic load probably due to strong gene flow; therefore, it is crucial to strengthen in situ habitat management for these two populations. By contrast, although human activities have a milder impact on MPA, it is at high risk of extinction due to long-term contraction and isolation, and genetic rescue is urgently needed. MPB1 exhibited a relatively healthy population status and can potentially serve as a source population. Overall, our findings provide novel insights into the conservation of the Chinese pangolin and biogeography of the mammals of eastern Asia.
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Globally, the majority of habitat loss is irreversible, and most species will never recover their former ranges. We have learned a great deal about what leads to population decline and extinction, but less about recovery. The recently downlisted giant panda provides a unique opportunity to understand the mechanisms of species recovery. In our study, we estimate giant panda suitable habitats, population density, and gene flow across landscapes to fully investigate the direct and indirect ecological mechanisms underlying bold conservation strategies. We found that the Giant Panda National Survey has modestly but systematically underestimated population size. China's effort to mitigate anthropogenic disturbances was associated with increased panda population density through improving habitat quality and reducing habitat fragmentation. Enhanced landscape connectivity reduced inbreeding via gene flow but indirectly increased inbreeding temporarily due to high local panda density. Although the panda's recovery has been geographically uneven, we provide evidence for improving connectivity and gene flow resulting from conservation efforts. If these processes can be sustained and improved, the panda's path to recovery will be less encumbered by loss of genetic diversity, fostering hope that the present rate of recovery will not be stalled. Findings from this study will not only help guide future giant panda conservation management but also provide a model for how a more mechanistic examination of the genetic processes underlying species recovery can foster the development of more effective strategies for endangered species recovery.
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Contemporary biodiversity patterns are shaped by not only modern climate but also factors such as past climate fluctuations. Investigating the relative degree of paleoclimate legacy could help us understand the formation of current biodiversity patterns. However, an assessment of this issue in China is lacking. Here, we investigated the phylogenetic structure and functional diversity patterns of Chinese terrestrial vertebrates. We found that Southern China harbored higher functional richness, while Northern and Western China were more phylogenetically clustered with higher functional divergence and evenness, indicating environmental filtering effects. Moreover, we found that drastic Last Glacial Maximum climate changes were positively related to phylogenetic clustering, lower functional richness, and higher functional divergence and evenness, although this effect varied among different taxonomic groups. We further found that mammal communities experiencing more drastic Last Glacial Maximum temperature changes were characterized by "faster" life-history trait values. Our findings provide new evidence of the paleoclimate change legacies influencing contemporary biodiversity patterns that will help guide national-level conservation plans.
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The orchid mantises achieve camouflage with morphological modifications in body color and pattern, providing an interesting model for understanding phenotypic innovation. However, a reference genome is lacking for the order Mantodea. To unveil the mechanisms of plant-mimicking body coloration and patterns, we performed de novo assembly of two chromosome-level genomes of the orchid mantis and its close relative, the dead leaf mantis. Comparative genomic analysis revealed that the Scarlet gene plays an important role in the synthesis of xanthommatin, an important pigment for mantis camouflage coloration. Combining developmental transcriptomic analysis and genetic engineering experiments, we found that the cuticle was an essential component of the 'petal-like' enlargement, and specific expression in the ventral femur was controlled by Wnt signaling. The prolonged expression of Ultrabithorax (Ubx) accompanied by femoral expansion suggested that Ubx determines leg remodeling in the early developmental stage. We also found evidence of evolution of the Trypsin gene family for insectivory adaptation and ecdysone-dependent sexual dimorphism in body size. Overall, our study presents new genome catalogs and reveals the genetic and evolutionary mechanisms underlying the unique camouflage of the praying mantis, providing evolutionary developmental insights into phenotypic innovation and adaptation.
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Mantódeos , Animais , Adaptação Fisiológica , GenômicaRESUMO
Bats are reservoirs for multiple coronaviruses (CoVs). However, the phylogenetic diversity and transmission of global bat-borne CoVs remain poorly understood. Here, we performed a Bayesian phylogeographic analysis based on 3,594 bat CoV RdRp gene sequences to study the phylogenetic diversity and transmission of bat-borne CoVs and the underlying driving factors. We found that host-switching events occurred more frequently for α-CoVs than for ß-CoVs, and the latter was highly constrained by bat phylogeny. Bat species in the families Molossidae, Rhinolophidae, Miniopteridae, and Vespertilionidae had larger contributions to the cross-species transmission of bat CoVs. Regions of eastern and southern Africa, southern South America, Western Europe, and Southeast Asia were more frequently involved in cross-region transmission events of bat CoVs than other regions. Phylogenetic and geographic distances were the most important factors limiting CoV transmission. Bat taxa and global geographic hotspots associated with bat CoV phylogenetic diversity were identified, and bat species richness, mean annual temperature, global agricultural cropland, and human population density were strongly correlated with the phylogenetic diversity of bat CoVs. These findings provide insight into bat CoV evolution and ecological transmission among bat taxa. The identified hotspots of bat CoV evolution and transmission will guide early warnings of bat-borne CoV zoonotic diseases.
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Betacoronavirus , Infecções por Coronavirus , Filogenia , Betacoronavirus/genética , Infecções por Coronavirus/transmissão , Animais , Quirópteros , Alphacoronavirus/genéticaRESUMO
BACKGROUND: The gut microbiota play important roles in host adaptation and evolution, but are understudied in natural population of wild mammals. To address host adaptive evolution and improve conservation efforts of threatened mammals from a metagenomic perspective, we established a high-quality gut microbiome catalog of the giant panda (pandaGUT) to resolve the microbiome diversity, functional, and resistome landscapes using approximately 7 Tbp of long- and short-read sequencing data from 439 stool samples. RESULTS: The pandaGUT catalog comprises 820 metagenome-assembled genomes, including 40 complete closed genomes, and 64.5% of which belong to species that have not been previously reported, greatly expanding the coverage of most prokaryotic lineages. The catalog contains 2.37 million unique genes, with 74.8% possessing complete open read frames, facilitating future mining of microbial functional potential. We identified three microbial enterotypes across wild and captive panda populations characterized by Clostridium, Pseudomonas, and Escherichia, respectively. We found that wild pandas exhibited host genetic-specific microbial structures and functions, suggesting host-gut microbiota phylosymbiosis, while the captive cohorts encoded more multi-drug resistance genes. CONCLUSIONS: Our study provides largely untapped resources for biochemical and biotechnological applications as well as potential intervention avenues via the rational manipulation of microbial diversity and reducing antibiotic usage for future conservation management of wildlife. Video Abstract.
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Microbioma Gastrointestinal , Microbiota , Animais , Microbiota/genética , Microbioma Gastrointestinal/genética , Animais Selvagens/microbiologia , Metagenoma/genética , Bactérias/genética , Mamíferos/genéticaRESUMO
Multiple factors influence gut microbiome diversity in vertebrate hosts. Most previous studies have only investigated specific factors and certain host species or taxa. However, a comprehensive assessment of the relative contributions of individual factors towards gut microbial diversity within a broader evolutionary context remains lacking. Here, 2202 16S rRNA gene sequencing samples of gut bacterial communities collected from 452 host species across seven classes were analyzed together to understand the factors broadly affecting vertebrate gut microbiomes across hosts with different diets, threatened status, captivity status, and habitat environmental factors. Among wild vertebrates, diet was most significantly associated with gut microbiome alpha diversity, while host phylogeny and diet were significantly associated with beta diversity, consistent with a previous study. Host threatened status and habitat environmental factors (e.g., geography and climate) were also associated with gut bacterial community beta diversity. Subsequent ecological modeling revealed a strong association between stochastic assembly processes and patterns of gut bacterial diversity among free-ranging vertebrates. In addition, metagenomic analysis of gut microbiomes from 62 captive vertebrates and sympatric humans revealed similar diversity and resistome profiles despite differences in host phylogeny, diet, and threatened status. These results thus suggest that captivity diminishes the effects of host phylogeny, diet, and threatened status on the diversity of vertebrate gut bacterial communities. The most overrepresented antibiotic resistant genes (ARGs) observed in these samples are involved in resistance to ß-lactams, aminoglycosides, and tetracycline. These results also revealed potential horizontal transfers of ARGs between captive animals and humans, thereby jointly threatening public health and vertebrate conservation. Together, this study provides a comprehensive overview of the diversity and resistomes of vertebrate gut microbiomes. These combined analyses will help guide future vertebrate conservation via the rational manipulation of microbial diversity and reducing antibiotic usage.
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Microbioma Gastrointestinal , Animais , Antibacterianos , Bactérias , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/genética , VertebradosRESUMO
The Convention on Biological Diversity (CBD) has launched two long-term, target-based conservation Strategic Plans in the past two decades. We compiled an index-based assessment framework to evaluate target achievements of the CBD using long-term indicators. The CBD Index is steadily increasing, with the Goal Indices for biodiversity mainstreaming, protection, and supporting mechanisms all improving over time. While the State and Pressure Indices continue to deteriorate coupled with human population and economic development, their changing rates have slowed down, most likely because of the constantly growing conservation efforts as revealed by the Response Index. The first quantitative assessment of the CBD's long-term performance may provide critical science-based evidence for continuing commitments to developing and implementing a new Post-2020 Global Biodiversity Framework. We also call for enhanced efforts to address the emerging challenges in achieving the 2050 Vision for Biodiversity and the adoption of a rapid assessment framework to track future progress.
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Characteristics of the gut microbiome vary synchronously with changes in host diet. However, the underlying effects of these fluctuations remain unclear. Here, we performed fecal microbiota transplantation (FMT) of diet-specific feces from an endangered mammal (the giant panda) into a germ-free mouse model. We demonstrated that the butyrate-producing bacterium Clostridium butyricum was more abundant during shoot-eating season than during the leaf-eating season, congruent with the significant increase in host body mass. Following season-specific FMT, the microbiota of the mouse model resembled that of the donor, and mice transplanted with the microbiota from the shoot-eating season grew faster and stored more fat. Mechanistic investigations revealed that butyrate extended the upregulation of hepatic circadian gene Per2, subsequently increasing phospholipid biosynthesis. Validation experiments further confirmed this causal relationship. This study demonstrated that seasonal shifts in the gut microbiome affect growth performance, facilitating a deeper understanding of host-microbe interactions in wild mammals.