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1.
Cell ; 186(21): 4496-4513, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37832524

Resumo

Plant-associated microbiota can extend plant immune system function, improve nutrient acquisition and availability, and alleviate abiotic stresses. Thus, naturally beneficial microbial therapeutics are enticing tools to improve plant productivity. The basic definition of plant microbiota across species and ecosystems, combined with the development of reductionist experimental models and the manipulation of plant phenotypes with microbes, has fueled interest in its translation to agriculture. However, the great majority of microbes exhibiting plant-productivity traits in the lab and greenhouse fail in the field. Therapeutic microbes must reach détente, the establishment of uneasy homeostasis, with the plant immune system, invade heterogeneous pre-established plant-associated communities, and persist in a new and potentially remodeled community. Environmental conditions can alter community structure and thus impact the engraftment of therapeutic microbes. We survey recent breakthroughs, challenges, and opportunities in translating beneficial microbes from the lab to the field.


Assuntos
Microbiota , Plantas , Agricultura , Fenótipo , Plantas/microbiologia , Microbiologia do Solo , Estresse Fisiológico , Ecossistema
2.
Cell ; 185(5): 761-763, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35245479

Resumo

Powdery mildew, a potentially severe crop disease, can be controlled by mlo mutations, which suppress fungal proliferation but typically also reduce yield. Li et al. (2022) demonstrate that productivity can be restored by overexpressing a host sugar transporter, thus offering a new option for economically and environmentally benign disease control.


Assuntos
Ascomicetos , Doenças das Plantas , Ascomicetos/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética
3.
Cell ; 182(3): 713-721.e9, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32778225

Resumo

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) threatens global public health. The development of a vaccine is urgently needed for the prevention and control of COVID-19. Here, we report the pilot-scale production of an inactivated SARS-CoV-2 vaccine candidate (BBIBP-CorV) that induces high levels of neutralizing antibodies titers in mice, rats, guinea pigs, rabbits, and nonhuman primates (cynomolgus monkeys and rhesus macaques) to provide protection against SARS-CoV-2. Two-dose immunizations using 2 µg/dose of BBIBP-CorV provided highly efficient protection against SARS-CoV-2 intratracheal challenge in rhesus macaques, without detectable antibody-dependent enhancement of infection. In addition, BBIBP-CorV exhibits efficient productivity and good genetic stability for vaccine manufacture. These results support the further evaluation of BBIBP-CorV in a clinical trial.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Avaliação Pré-Clínica de Medicamentos/métodos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas de Produtos Inativados/uso terapêutico , Vacinas Virais/uso terapêutico , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/genética , COVID-19 , Vacinas contra COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/virologia , Modelos Animais de Doenças , Feminino , Cobaias , Imunogenicidade da Vacina , Macaca fascicularis , Macaca mulatta , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Filogenia , Pneumonia Viral/virologia , Coelhos , Ratos , Ratos Wistar , SARS-CoV-2 , Vacinas de Produtos Inativados/efeitos adversos , Células Vero , Vacinas Virais/efeitos adversos
4.
Cell ; 169(6): 983-984, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575678

Resumo

Selection of plants with traits that are beneficial for cultivation and consumption has been a common practice for thousands of years; however, combination of these traits can be detrimental too, for instance by leading to undesirable branching and yield loss in tomato. The findings from Soyk et al. in this issue of Cell help understand how to bypass such negative effects and improve crop productivity.


Assuntos
Fenótipo , Plantas , Regulação da Expressão Gênica
5.
Cell ; 169(4): 587-596, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28475891

Resumo

The phytobiome is composed of plants, their environment, and diverse interacting microscopic and macroscopic organisms, which together influence plant health and productivity. These organisms form complex networks that are established and regulated through nutrient cycling, competition, antagonism, and chemical communication mediated by a diverse array of signaling molecules. Integration of knowledge of signaling mechanisms with that of phytobiome members and their networks will lead to a new understanding of the fate and significance of these signals at the ecosystem level. Such an understanding could lead to new biological, chemical, and breeding strategies to improve crop health and productivity.


Assuntos
Ecossistema , Plantas/microbiologia , Animais , Artrópodes/fisiologia , Eucariotos/fisiologia , Nematoides/fisiologia , Fenômenos Fisiológicos Vegetais , Transdução de Sinais
6.
Cell ; 171(2): 470-480.e8, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28919077

Resumo

Major advances in crop yields are needed in the coming decades. However, plant breeding is currently limited by incremental improvements in quantitative traits that often rely on laborious selection of rare naturally occurring mutations in gene-regulatory regions. Here, we demonstrate that CRISPR/Cas9 genome editing of promoters generates diverse cis-regulatory alleles that provide beneficial quantitative variation for breeding. We devised a simple genetic scheme, which exploits trans-generational heritability of Cas9 activity in heterozygous loss-of-function mutant backgrounds, to rapidly evaluate the phenotypic impact of numerous promoter variants for genes regulating three major productivity traits in tomato: fruit size, inflorescence branching, and plant architecture. Our approach allows immediate selection and fixation of novel alleles in transgene-free plants and fine manipulation of yield components. Beyond a platform to enhance variation for diverse agricultural traits, our findings provide a foundation for dissecting complex relationships between gene-regulatory changes and control of quantitative traits.


Assuntos
Produtos Agrícolas/genética , Edição de Genes , Genoma de Planta , Sistemas CRISPR-Cas , Regiões Promotoras Genéticas , Locos de Características Quantitativas
7.
Cell ; 169(6): 1142-1155.e12, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28528644

Resumo

Selection for inflorescence architecture with improved flower production and yield is common to many domesticated crops. However, tomato inflorescences resemble wild ancestors, and breeders avoided excessive branching because of low fertility. We found branched variants carry mutations in two related transcription factors that were selected independently. One founder mutation enlarged the leaf-like organs on fruits and was selected as fruit size increased during domestication. The other mutation eliminated the flower abscission zone, providing "jointless" fruit stems that reduced fruit dropping and facilitated mechanical harvesting. Stacking both beneficial traits caused undesirable branching and sterility due to epistasis, which breeders overcame with suppressors. However, this suppression restricted the opportunity for productivity gains from weak branching. Exploiting natural and engineered alleles for multiple family members, we achieved a continuum of inflorescence complexity that allowed breeding of higher-yielding hybrids. Characterizing and neutralizing similar cases of negative epistasis could improve productivity in many agricultural organisms. VIDEO ABSTRACT.


Assuntos
Epistasia Genética , Proteínas de Domínio MADS/genética , Proteínas de Plantas/genética , Solanum lycopersicum/genética , Sequência de Aminoácidos , Domesticação , Inflorescência/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/fisiologia , Proteínas de Domínio MADS/química , Proteínas de Domínio MADS/metabolismo , Meristema/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
8.
Annu Rev Genet ; 57: 411-434, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-37722685

Resumo

Symbiotic interactions occur in all domains of life, providing organisms with resources to adapt to new habitats. A prime example is the endosymbiosis between corals and photosynthetic dinoflagellates. Eukaryotic dinoflagellate symbionts reside inside coral cells and transfer essential nutrients to their hosts, driving the productivity of the most biodiverse marine ecosystem. Recent advances in molecular and genomic characterization have revealed symbiosis-specific genes and mechanisms shared among symbiotic cnidarians. In this review, we focus on the cellular and molecular processes that underpin the interaction between symbiont and host. We discuss symbiont acquisition via phagocytosis, modulation of host innate immunity, symbiont integration into host cell metabolism, and nutrient exchange as a fundamental aspect of stable symbiotic associations. We emphasize the importance of using model systems to dissect the cellular complexity of endosymbiosis, which ultimately serves as the basis for understanding its ecology and capacity to adapt in the face of climate change.


Assuntos
Antozoários , Dinoflagellida , Animais , Antozoários/genética , Simbiose/genética , Ecossistema , Dinoflagellida/genética , Análise de Sistemas
9.
CA Cancer J Clin ; 73(5): 524-545, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37158423

Resumo

Increased attention to the rehabilitation needs of children with cancer is vital to enhance health, quality-of-life, and productivity outcomes. Among adults with cancer, rehabilitation recommendations are frequently incorporated into guidelines, but the extent to which recommendations exist for children is unknown. Reports included in this systematic review are guideline or expert consensus reports containing recommendations related to rehabilitation referral, evaluation, and/or intervention for individuals diagnosed with cancer during childhood (younger than 18 years). Eligible reports were published in English from January 2000 to August 2022. Through database searches, 42,982 records were identified; 62 records were identified through citation and website searching. Twenty-eight reports were included in the review: 18 guidelines and 10 expert consensus reports. Rehabilitation recommendations were identified in disease-specific (e.g., acute lymphoblastic leukemia), impairment-specific (e.g., fatigue, neurocognition, pain), adolescent and young adult, and long-term follow-up reports. Example recommendations included physical activity and energy-conservation techniques to address fatigue, referral to physical therapy for chronic pain management, ongoing psychosocial surveillance, and referral to speech-language pathology for those with hearing loss. High-level evidence supported rehabilitation recommendations for long-term follow-up care, fatigue, and psychosocial/mental health screening. Few intervention recommendations were included in guideline and consensus reports. In this developing field, it is critical to include pediatric oncology rehabilitation providers in guideline and consensus development initiatives. This review enhances the availability and clarity of rehabilitation-relevant guidelines that can help prevent and mitigate cancer-related disability among children by supporting access to rehabilitation services.


Assuntos
Exercício Físico , Neoplasias , Adolescente , Humanos , Criança , Consenso , Atenção à Saúde , Oncologia
10.
Nature ; 627(8005): 797-804, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38480894

Resumo

Evidence shows a continuing increase in the frequency and severity of global heatwaves1,2, raising concerns about the future impacts of climate change and the associated socioeconomic costs3,4. Here we develop a disaster footprint analytical framework by integrating climate, epidemiological and hybrid input-output and computable general equilibrium global trade models to estimate the midcentury socioeconomic impacts of heat stress. We consider health costs related to heat exposure, the value of heat-induced labour productivity loss and indirect losses due to economic disruptions cascading through supply chains. Here we show that the global annual incremental gross domestic product loss increases exponentially from 0.03 ± 0.01 (SSP 245)-0.05 ± 0.03 (SSP 585) percentage points during 2030-2040 to 0.05 ± 0.01-0.15 ± 0.04 percentage points during 2050-2060. By 2060, the expected global economic losses reach a total of 0.6-4.6% with losses attributed to health loss (37-45%), labour productivity loss (18-37%) and indirect loss (12-43%) under different shared socioeconomic pathways. Small- and medium-sized developing countries suffer disproportionately from higher health loss in South-Central Africa (2.1 to 4.0 times above global average) and labour productivity loss in West Africa and Southeast Asia (2.0-3.3 times above global average). The supply-chain disruption effects are much more widespread with strong hit to those manufacturing-heavy countries such as China and the USA, leading to soaring economic losses of 2.7 ± 0.7% and 1.8 ± 0.5%, respectively.

11.
Nature ; 627(8003): 328-334, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38480966

Resumo

As airborne methane surveys of oil and gas systems continue to discover large emissions that are missing from official estimates1-4, the true scope of methane emissions from energy production has yet to be quantified. We integrate approximately one million aerial site measurements into regional emissions inventories for six regions in the USA, comprising 52% of onshore oil and 29% of gas production over 15 aerial campaigns. We construct complete emissions distributions for each, employing empirically grounded simulations to estimate small emissions. Total estimated emissions range from 0.75% (95% confidence interval (CI) 0.65%, 0.84%) of covered natural gas production in a high-productivity, gas-rich region to 9.63% (95% CI 9.04%, 10.39%) in a rapidly expanding, oil-focused region. The six-region weighted average is 2.95% (95% CI 2.79%, 3.14%), or roughly three times the national government inventory estimate5. Only 0.05-1.66% of well sites contribute the majority (50-79%) of well site emissions in 11 out of 15 surveys. Ancillary midstream facilities, including pipelines, contribute 18-57% of estimated regional emissions, similarly concentrated in a small number of point sources. Together, the emissions quantified here represent an annual loss of roughly US$1 billion in commercial gas value and a US$9.3 billion annual social cost6. Repeated, comprehensive, regional remote-sensing surveys offer a path to detect these low-frequency, high-consequence emissions for rapid mitigation, incorporation into official emissions inventories and a clear-eyed assessment of the most effective emission-finding technologies for a given region.

12.
Nature ; 629(8012): 603-608, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38750234

Resumo

Natural iron fertilization of the Southern Ocean by windblown dust has been suggested to enhance biological productivity and modulate the climate1-3. Yet, this process has never been quantified across the Southern Ocean and at annual timescales4,5. Here we combined 11 years of nitrate observations from autonomous biogeochemical ocean profiling floats with a Southern Hemisphere dust simulation to empirically derive the relationship between dust-iron deposition and annual net community production (ANCP) in the iron-limited Southern Ocean. Using this relationship, we determined the biological response to dust-iron in the pelagic perennially ice-free Southern Ocean at present and during the last glacial maximum (LGM). We estimate that dust-iron now supports 33% ± 15% of Southern Ocean ANCP. During the LGM, when dust deposition was 5-40-fold higher than today, the contribution of dust to Southern Ocean ANCP was much greater, estimated at 64% ± 13%. We provide quantitative evidence of basin-wide dust-iron fertilization of the Southern Ocean and the potential magnitude of its impact on glacial-interglacial timescales, supporting the idea of the important role of dust in the global carbon cycle and climate6-8.


Assuntos
Ciclo do Carbono , Clima , Poeira , Ferro , Oceanos e Mares , Água do Mar , Poeira/análise , Camada de Gelo , Ferro/análise , Nitratos/análise , Água do Mar/química
13.
Nature ; 630(8018): 920-925, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38867040

Resumo

Working from home has become standard for employees with a university degree. The most common scheme, which has been adopted by around 100 million employees in Europe and North America, is a hybrid schedule, in which individuals spend a mix of days at home and at work each week1,2. However, the effects of hybrid working on employees and firms have been debated, and some executives argue that it damages productivity, innovation and career development3-5. Here we ran a six-month randomized control trial investigating the effects of hybrid working from home on 1,612 employees in a Chinese technology company in 2021-2022. We found that hybrid working improved job satisfaction and reduced quit rates by one-third. The reduction in quit rates was significant for non-managers, female employees and those with long commutes. Null equivalence tests showed that hybrid working did not affect performance grades over the next two years of reviews. We found no evidence for a difference in promotions over the next two years overall, or for any major employee subgroup. Finally, null equivalence tests showed that hybrid working had no effect on the lines of code written by computer-engineer employees. We also found that the 395 managers in the experiment revised their surveyed views about the effect of hybrid working on productivity, from a perceived negative effect (-2.6% on average) before the experiment to a perceived positive one (+1.0%) after the experiment. These results indicate that a hybrid schedule with two days a week working from home does not damage performance.


Assuntos
Satisfação no Emprego , Reorganização de Recursos Humanos , Teletrabalho , Desempenho Profissional , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , China , Eficiência , Reorganização de Recursos Humanos/estatística & dados numéricos , Teletrabalho/estatística & dados numéricos , Desempenho Profissional/estatística & dados numéricos , Tolerância ao Trabalho Programado/psicologia , Tecnologia , Comércio , Mobilidade Ocupacional
14.
Nature ; 626(7998): 335-340, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38233526

Resumo

Predators have a key role in structuring ecosystems1-4. However, predator loss is accelerating globally4-6, and predator mass-mortality events7 (MMEs)-rapid large-scale die-offs-are now emblematic of the Anthropocene epoch6. Owing to their rare and unpredictable nature7, we lack an understanding of how MMEs immediately impact ecosystems. Past predator-removal studies2,3 may be insufficient to understand the ecological consequences of MMEs because, in nature, dead predators decompose in situ and generate a resource pulse8, which could alter ensuing ecosystem dynamics by temporarily enhancing productivity. Here we experimentally induce MMEs in tritrophic, freshwater lake food webs and report ecological dynamics that are distinct from predator losses2,3 or resource pulses9 alone, but that can be predicted from theory8. MMEs led to the proliferation of diverse consumer and producer communities resulting from weakened top-down predator control1-3 and stronger bottom-up effects through predator decomposition8. In contrast to predator removals alone, enhanced primary production after MMEs dampened the consumer community response. As a consequence, MMEs generated biomass dynamics that were most similar to those of undisturbed systems, indicating that they may be cryptic disturbances in nature. These biomass dynamics led to trophic decoupling, whereby the indirect beneficial effects of predators on primary producers are lost and later materialize as direct bottom-up effects that stimulate primary production amid intensified herbivory. These results reveal ecological signatures of MMEs and demonstrate the feasibility of forecasting novel ecological dynamics arising with intensifying global change.


Assuntos
Biomassa , Ecologia , Cadeia Alimentar , Comportamento Predatório , Animais , Herbivoria/fisiologia , Lagos , Comportamento Predatório/fisiologia , Densidade Demográfica , Previsões , Ecologia/métodos , Mudança Climática
15.
Nature ; 627(8002): 49-58, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38448693

Resumo

Scientists are enthusiastically imagining ways in which artificial intelligence (AI) tools might improve research. Why are AI tools so attractive and what are the risks of implementing them across the research pipeline? Here we develop a taxonomy of scientists' visions for AI, observing that their appeal comes from promises to improve productivity and objectivity by overcoming human shortcomings. But proposed AI solutions can also exploit our cognitive limitations, making us vulnerable to illusions of understanding in which we believe we understand more about the world than we actually do. Such illusions obscure the scientific community's ability to see the formation of scientific monocultures, in which some types of methods, questions and viewpoints come to dominate alternative approaches, making science less innovative and more vulnerable to errors. The proliferation of AI tools in science risks introducing a phase of scientific enquiry in which we produce more but understand less. By analysing the appeal of these tools, we provide a framework for advancing discussions of responsible knowledge production in the age of AI.


Assuntos
Inteligência Artificial , Ilusões , Conhecimento , Projetos de Pesquisa , Pesquisadores , Humanos , Inteligência Artificial/provisão & distribuição , Inteligência Artificial/tendências , Cognição , Difusão de Inovações , Eficiência , Reprodutibilidade dos Testes , Projetos de Pesquisa/normas , Projetos de Pesquisa/tendências , Risco , Pesquisadores/psicologia , Pesquisadores/normas
16.
Nature ; 621(7978): 330-335, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37587345

Resumo

Projected responses of ocean net primary productivity to climate change are highly uncertain1. Models suggest that the climate sensitivity of phytoplankton nutrient limitation in the low-latitude Pacific Ocean plays a crucial role1-3, but this is poorly constrained by observations4. Here we show that changes in physical forcing drove coherent fluctuations in the strength of equatorial Pacific iron limitation through multiple El Niño/Southern Oscillation (ENSO) cycles, but that this was overestimated twofold by a state-of-the-art climate model. Our assessment was enabled by first using a combination of field nutrient-addition experiments, proteomics and above-water hyperspectral radiometry to show that phytoplankton physiological responses to iron limitation led to approximately threefold changes in chlorophyll-normalized phytoplankton fluorescence. We then exploited the >18-year satellite fluorescence record to quantify climate-induced nutrient limitation variability. Such synoptic constraints provide a powerful approach for benchmarking the realism of model projections of net primary productivity to climate changes.


Assuntos
Modelos Climáticos , El Niño Oscilação Sul , Ferro , Clorofila/metabolismo , Mudança Climática , Fluorescência , Ferro/metabolismo , Nutrientes/metabolismo , Oceano Pacífico , Fitoplâncton/metabolismo , Proteômica , Radiometria , Imagens de Satélites
17.
Nature ; 619(7970): 521-525, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37380780

Resumo

The oxygen content of the oceans is susceptible to climate change and has declined in recent decades1, with the largest effect in oxygen-deficient zones (ODZs)2, that is, mid-depth ocean regions with oxygen concentrations <5 µmol kg-1 (ref. 3). Earth-system-model simulations of climate warming predict that ODZs will expand until at least 2100. The response on timescales of hundreds to thousands of years, however, remains uncertain3-5. Here we investigate changes in the response of ocean oxygenation during the warmer-than-present Miocene Climatic Optimum (MCO; 17.0-14.8 million years ago (Ma)). Our planktic foraminifera I/Ca and δ15N data, palaeoceanographic proxies sensitive to ODZ extent and intensity, indicate that dissolved-oxygen concentrations in the eastern tropical Pacific (ETP) exceeded 100 µmol kg-1 during the MCO. Paired Mg/Ca-derived temperature data suggest that an ODZ developed in response to an increased west-to-east temperature gradient and shoaling of the ETP thermocline. Our records align with model simulations of data from recent decades to centuries6,7, suggesting that weaker equatorial Pacific trade winds during warm periods may lead to decreased upwelling in the ETP, causing equatorial productivity and subsurface oxygen demand to be less concentrated in the east. These findings shed light on how warm-climate states such as during the MCO may affect ocean oxygenation. If the MCO is considered as a possible analogue for future warming, our findings seem to support models suggesting that the recent deoxygenation trend and expansion of the ETP ODZ may eventually reverse3,4.


Assuntos
Oxigênio , Água do Mar , Clima Tropical , Mudança Climática/história , Mudança Climática/estatística & dados numéricos , Oxigênio/análise , Oxigênio/história , Oceano Pacífico , Água do Mar/química , História Antiga , História do Século XXI , Modelos Climáticos , Foraminíferos/isolamento & purificação , Mapeamento Geográfico , Incerteza
18.
Nature ; 620(7975): 824-829, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532931

Resumo

The fossil record of cetaceans documents how terrestrial animals acquired extreme adaptations and transitioned to a fully aquatic lifestyle1,2. In whales, this is associated with a substantial increase in maximum body size. Although an elongate body was acquired early in cetacean evolution3, the maximum body mass of baleen whales reflects a recent diversification that culminated in the blue whale4. More generally, hitherto known gigantism among aquatic tetrapods evolved within pelagic, active swimmers. Here we describe Perucetus colossus-a basilosaurid whale from the middle Eocene epoch of Peru. It displays, to our knowledge, the highest degree of bone mass increase known to date, an adaptation associated with shallow diving5. The estimated skeletal mass of P. colossus exceeds that of any known mammal or aquatic vertebrate. We show that the bone structure specializations of aquatic mammals are reflected in the scaling of skeletal fraction (skeletal mass versus whole-body mass) across the entire disparity of amniotes. We use the skeletal fraction to estimate the body mass of P. colossus, which proves to be a contender for the title of heaviest animal on record. Cetacean peak body mass had already been reached around 30 million years before previously assumed, in a coastal context in which primary productivity was particularly high.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Peso Corporal , Fósseis , Baleias , Animais , Aclimatação , Peru , Baleias/anatomia & histologia , Baleias/classificação , Baleias/fisiologia , Tamanho Corporal , Esqueleto , Mergulho
19.
Nature ; 620(7974): 562-569, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37587299

Resumo

Glacier shrinkage and the development of post-glacial ecosystems related to anthropogenic climate change are some of the fastest ongoing ecosystem shifts, with marked ecological and societal cascading consequences1-6. Yet, no complete spatial analysis exists, to our knowledge, to quantify or anticipate this important changeover7,8. Here we show that by 2100, the decline of all glaciers outside the Antarctic and Greenland ice sheets may produce new terrestrial, marine and freshwater ecosystems over an area ranging from the size of Nepal (149,000 ± 55,000 km2) to that of Finland (339,000 ± 99,000 km2). Our analysis shows that the loss of glacier area will range from 22 ± 8% to 51 ± 15%, depending on the climate scenario. In deglaciated areas, the emerging ecosystems will be characterized by extreme to mild ecological conditions, offering refuge for cold-adapted species or favouring primary productivity and generalist species. Exploring the future of glacierized areas highlights the importance of glaciers and emerging post-glacial ecosystems in the face of climate change, biodiversity loss and freshwater scarcity. We find that less than half of glacial areas are located in protected areas. Echoing the recent United Nations resolution declaring 2025 as the International Year of Glaciers' Preservation9 and the Global Biodiversity Framework10, we emphasize the need to urgently and simultaneously enhance climate-change mitigation and the in situ protection of these ecosystems to secure their existence, functioning and values.


Assuntos
Ecossistema , Aquecimento Global , Camada de Gelo , Biodiversidade , Água Doce/análise , Aquecimento Global/legislação & jurisprudência , Aquecimento Global/prevenção & controle , Nações Unidas/legislação & jurisprudência , Análise Espaço-Temporal , Especificidade da Espécie , Animais
20.
Nature ; 620(7974): 625-633, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37495698

Resumo

Most bacteria in the biosphere are predicted to be polylysogens harbouring multiple prophages1-5. In studied systems, prophage induction from lysogeny to lysis is near-universally driven by DNA-damaging agents6. Thus, how co-residing prophages compete for cell resources if they respond to an identical trigger is unknown. Here we discover regulatory modules that control prophage induction independently of the DNA-damage cue. The modules bear little resemblance at the sequence level but share a regulatory logic by having a transcription factor that activates the expression of a neighbouring gene that encodes a small protein. The small protein inactivates the master repressor of lysis, which leads to induction. Polylysogens that harbour two prophages exposed to DNA damage release mixed populations of phages. Single-cell analyses reveal that this blend is a consequence of discrete subsets of cells producing one, the other or both phages. By contrast, induction through the DNA-damage-independent module results in cells producing only the phage sensitive to that specific cue. Thus, in the polylysogens tested, the stimulus used to induce lysis determines phage productivity. Considering the lack of potent DNA-damaging agents in natural habitats, additional phage-encoded sensory pathways to lysis likely have fundamental roles in phage-host biology and inter-prophage competition.


Assuntos
Bactérias , Bacteriófagos , Lisogenia , Prófagos , Proteínas Virais , Bacteriófagos/genética , Bacteriófagos/metabolismo , Lisogenia/genética , Prófagos/genética , Prófagos/metabolismo , Proteínas Virais/metabolismo , Ativação Viral/genética , Bactérias/virologia , Dano ao DNA , DNA Viral/genética , DNA Viral/metabolismo , Análise de Célula Única , Fatores de Transcrição/metabolismo , Interações Hospedeiro-Patógeno
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