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1.
Braz. j. biol ; 84: e260090, 2024. graf
Artigo em Inglês | VETINDEX | ID: biblio-1374700

RESUMO

Ophiactis savignyi could be discovered all over the world in tropical marine environments. People could have aided in the spread of O. savignyi, particularly in the western and eastern populations of Panama's Isthmus. The brittle star Ophiactis savignyi, often known as savigny's brittle star, coexists alongside the sponge Geodia corticostylifera. The focus of this research has been to assess the functional relevance of G. corticostylifera secondary metabolites as antifoulant against mussels, protection against generalist fish, and chemical cues to affiliated brittle stars. Both in flow-through and static seawater laboratory studies, O. savignyi which has previously been connected with sponges, was given both treated and control mimics at the same time. The sponge extract was also tested for its ability to protect fish against predators and fouling. Deterrence test using chemicals indicated that the normal level of the sponge extract may also suppress generalist fish predation in the field as well as the mussel Perna perna's normal attachment in clinical contexts. According to the findings, G. corticostylifera crude extract has many roles in the aquatic environments, apparently being accountable for this sponge's tighter relationship with O. savignyi, which protects the ophiuroid and inhibits epibionts on itself.


Ophiactis savignyi pode ser descoberta em todo o mundo em ambientes marinhos tropicais. A população pode ter contribuído para a propagação de O. savignyi, particularmente as populações ocidentais e orientais do istmo do Panamá. A estrela-quebradiça O. savignyi, muitas vezes conhecida como estrela-quebradiça de Savignyi, coexiste com a esponja Geodia corticostylifera. O foco desta pesquisa foi avaliar a relevância funcional dos metabólitos secundários de G. corticostylifera como anti-incrustante contra mexilhões, proteção contra peixes generalistas e sinais químicos para estrelas-quebradiças afiliadas. Em estudos de laboratório com fluxo contínuo e estático de água do mar, O. savignyi, que anteriormente havia se ligado a esponjas, recebeu mimetizadores tratados e controle ao mesmo tempo. O extrato de esponja também foi testado por sua capacidade de proteger os peixes contra predadores e incrustações. Testes de dissuasão usando produtos químicos indicaram que o nível normal de extrato de esponja também pode suprimir a predação de peixes generalistas no campo, bem como a fixação normal do mexilhão Perna perna em ambientes clínicos. De acordo com os achados, o extrato bruto de G. corticostylifera tem diversas funções em ambientes aquáticos, aparentemente responsáveis ​​pela relação mais próxima dessa esponja com O. savignyi, protegendo o ofiuroide e inibindo os epibiontes.


Assuntos
Animais , Poríferos/parasitologia , Simbiose , Bactérias , Geodia/parasitologia
2.
Nat Commun ; 14(1): 323, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658193

RESUMO

In plants, the topological organization of membranes has mainly been attributed to the cell wall and the cytoskeleton. Additionally, few proteins, such as plant-specific remorins have been shown to function as protein and lipid organizers. Root nodule symbiosis requires continuous membrane re-arrangements, with bacteria being finally released from infection threads into membrane-confined symbiosomes. We found that mutations in the symbiosis-specific SYMREM1 gene result in highly disorganized perimicrobial membranes. AlphaFold modelling and biochemical analyses reveal that SYMREM1 oligomerizes into antiparallel dimers and may form a higher-order membrane scaffolding structure. This was experimentally confirmed when expressing this and other remorins in wall-less protoplasts is sufficient where they significantly alter and stabilize de novo membrane topologies ranging from membrane blebs to long membrane tubes with a central actin filament. Reciprocally, mechanically induced membrane indentations were equally stabilized by SYMREM1. Taken together we describe a plant-specific mechanism that allows the stabilization of large-scale membrane conformations independent of the cell wall.


Assuntos
Proteínas de Transporte , Fosfoproteínas , Proteínas de Transporte/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Simbiose
3.
Evolution ; 77(1): 166-185, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36622711

RESUMO

Many interspecific interactions are shaped by coevolution. Transmission mode is thought to influence opportunities for coevolution within symbiotic interactions. Vertical transmission maintains partner fidelity, increasing opportunities for coevolution, but horizontal transmission may disrupt partner fidelity, potentially reducing opportunities for coevolution. Despite these predictions, the role of coevolution in the maintenance of horizontally transmitted symbioses is unclear. Leveraging a tractable insect-bacteria symbiosis, we tested for signatures of pairwise coevolution by assessing patterns of host-symbiont specialization. If pairwise coevolution defines the interaction, we expected to observe evidence of reciprocal specialization between hosts and their local symbionts. We found no evidence for local adaptation between sympatric lineages of Anasa tristis squash bugs and Caballeronia spp. symbionts across their native geographic range. We also found no evidence for specialization between three co-localized Anasa host species and their native Caballeronia symbionts. Our results demonstrate generalist dynamics underlie the interaction between Anasa insect hosts and their Caballeronia symbionts. We predict that selection from multiple host species may favor generalist symbiont traits through diffuse coevolution. Alternatively, selection for generalist traits may be a consequence of selection by hosts for fixed cooperative symbiont traits without coevolution.


Assuntos
Bactérias , Simbiose , Animais , Adaptação Fisiológica , Aclimatação , Insetos
4.
Sci Adv ; 9(2): eade1150, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36638166

RESUMO

Symbiotic nitrogen fixation boosts legume growth and production in nitrogen-poor soils. It has long been assumed that fixed nitrogen increases reproductive success, but until now, the regulatory mechanism was unknown. Here, we report a symbiotic flowering pathway that couples symbiotic and nutrient signals to the flowering induction pathway in legumes. We show that the symbiotic microRNA-microRNA172c (miR172c) and fixed nitrogen systemically and synergistically convey symbiotic and nutritional cues from roots to leaves to promote soybean (Glycine max) flowering. The combinations of symbiotic miR172c and local miR172c elicited by fixed nitrogen and development in leaves activate florigen-encoding FLOWERING LOCUS T (FT) homologs (GmFT2a/5a) by repressing TARGET OF EAT1-like 4a (GmTOE4a). Thus, FTs trigger reproductive development, which allows legumes to survive and reproduce under low-nitrogen conditions.


Assuntos
Fixação de Nitrogênio , Soja , Nitrogênio/metabolismo , Fixação de Nitrogênio/fisiologia , Soja/genética , Simbiose/fisiologia , MicroRNAs , RNA de Plantas , Genes de Plantas
5.
J Exp Med ; 220(3)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36688957

RESUMO

Gut microbiota contain communities of viruses, bacteria, fungi, and Eukarya, and live as biofilms. In health, these biofilms adhere to the intestinal mucus surface without contacting the epithelium. Disruptions to the equilibrium between these biofilms and the host may create invasive pathobionts from these commensal communities and contribute to disease pathogenesis. Environmental factors appear to dominate over genetics in determining the shifts in microbiota populations and function, including when comparing microbiota between low-income and industrialized countries. The observations discussed herein carry enormous potential for the development of novel therapies targeting phenotype in microbiota dysbiosis.


Assuntos
Microbioma Gastrointestinal , Microbiota , Humanos , Biofilmes , Bactérias , Simbiose , Disbiose/microbiologia
6.
Philos Trans R Soc Lond B Biol Sci ; 378(1872): 20210408, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36688400

RESUMO

That humans might undergo future evolutionary transitions in individuality (ETIs) seems fanciful. However, drawing upon recent thinking concerning the origins of properties that underpin ETIs, I argue that certain ETIs are imminently realizable. Central to my argument is recognition that heritable variance in fitness at higher levels of organization can be externally imposed (scaffolded) by specific ecological structures and cultural practices. While ETIs to eusociality seem highly improbable, ETIs involving symbioses between humans and artificial intelligence (AI) can be readily envisaged. A necessary requirement is that fitness-affecting interactions between humans and AI devices are inherited by offspring. The Mendelian nature of human reproduction ensures that offspring resemble parents. Reproduction of AI devices requires nothing more than transference of algorithms from parental AI devices to devices that are assigned to offspring. This simple copying, combined with societal structures that require humans to carry AI devices, ensures heritable variance in fitness at the level of both interacting partners. Selection at the collective level will drive alignment of replicative fates and increase co-dependency, thus alleviating need for continual imposition of externally imposed scaffolds. I conclude by drawing attention to the immediacy of such transitions and express concern over possibilities for malevolent manipulation. This article is part of the theme issue 'Human socio-cultural evolution in light of evolutionary transitions'.


Assuntos
Inteligência Artificial , Evolução Biológica , Humanos , Reprodução , Algoritmos , Simbiose
7.
Sci Rep ; 13(1): 116, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596823

RESUMO

The salinity of soil is a relevant environmental problem around the world, with climate change raising its relevance, particularly in arid and semiarid areas. Arbuscular Mycorrhizal Fungi (AMF) positively affect plant growth and health by mitigating biotic and abiotic stresses, including salt stress. The mechanisms through which these benefits manifest are, however, still unclear. This work aimed to identify key genes involved in the response to salt stress induced by AMF using RNA-Seq analysis on durum wheat (Triticum turgidum L. subsp. durum Desf. Husn.). Five hundred sixty-three differentially expressed genes (DEGs), many of which involved in pathways related to plant stress responses, were identified. The expression of genes involved in trehalose metabolism, RNA processing, vesicle trafficking, cell wall organization, and signal transduction was significantly enhanced by the AMF symbiosis. A downregulation of genes involved in both enzymatic and non-enzymatic oxidative stress responses as well as amino acids, lipids, and carbohydrates metabolisms was also detected, suggesting a lower oxidative stress condition in the AMF inoculated plants. Interestingly, many transcription factor families, including WRKY, NAC, and MYB, already known for their key role in plant abiotic stress response, were found differentially expressed between treatments. This study provides valuable insights on AMF-induced gene expression modulation and the beneficial effects of plant-AMF interaction in durum wheat under salt stress.


Assuntos
Micorrizas , Transcriptoma , Triticum/metabolismo , Simbiose/fisiologia , Raízes de Plantas/metabolismo , Tolerância ao Sal/genética , Micorrizas/fisiologia
8.
Sci Rep ; 13(1): 375, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36611035

RESUMO

Symbiotic associations are dynamic systems influenced by both intrinsic and extrinsic factors. Here we describe for the first time the developmental and seasonal changes of the funicular bodies in the bryozoan Dendrobeania fruticosa, which are unique temporary organs of cheilostome bryozoans containing prokaryotic symbionts. Histological and ultrastructural studies showed that these organs undergo strong seasonal modification in the White Sea during the ice-free period. Initially (in June) they play a trophic function and support the development of a large population of bacteria. From June to September, both funicular bodies and bacteria show signs of degradation accompanied by development of presumed virus-like particles (VLPs); these self-organize to hollow spheres inside bacteria and are also detected outside of them. Although the destruction of bacteria coincides with the development of VLPs and spheres, the general picture differs considerably from the known instances of bacteriophagy in bryozoans. We broadly discuss potential routes of bacterial infection in Bryozoa and question the hypothesis of vertical transfer, which, although widely accepted in the literature, is contradicted by molecular, morphological and ecological evidence.


Assuntos
Briozoários , Animais , Briozoários/ultraestrutura , Estações do Ano , Simbiose
9.
Commun Biol ; 6(1): 66, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36653505

RESUMO

Ocean acidification caused by shifts in ocean carbonate chemistry resulting from increased atmospheric CO2 concentrations is threatening many calcifying organisms, including corals. Here we assessed autotrophy vs heterotrophy shifts in the Mediterranean zooxanthellate scleractinian coral Balanophyllia europaea acclimatized to low pH/high pCO2 conditions at a CO2 vent off Panarea Island (Italy). Dinoflagellate endosymbiont densities were higher at lowest pH Sites where changes in the distribution of distinct haplotypes of a host-specific symbiont species, Philozoon balanophyllum, were observed. An increase in symbiont C/N ratios was observed at low pH, likely as a result of increased C fixation by higher symbiont cell densities. δ13C values of the symbionts and host tissue reached similar values at the lowest pH Site, suggesting an increased influence of autotrophy with increasing acidification. Host tissue δ15N values of 0‰ strongly suggest that diazotroph N2 fixation is occurring within the coral tissue/mucus at the low pH Sites, likely explaining the decrease in host tissue C/N ratios with acidification. Overall, our findings show an acclimatization of this coral-dinoflagellate mutualism through trophic adjustment and symbiont haplotype differences with increasing acidification, highlighting that some corals are capable of acclimatizing to ocean acidification predicted under end-of-century scenarios.


Assuntos
Antozoários , Dinoflagelados , Animais , Dióxido de Carbono , Concentração de Íons de Hidrogênio , Água do Mar/química , Simbiose , Dinoflagelados/genética , Aclimatação
10.
Microbiome ; 11(1): 12, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36670449

RESUMO

BACKGROUND: The plasmid-mediated resistance gene mcr-1 confers colistin resistance in Escherichia coli and paves the way for the evolution to pan-drug resistance. We investigated the impact of mcr-1 in gut colonization in the absence of antibiotics using isogenic E. coli strains transformed with a plasmid encoding or devoid of mcr-1. RESULTS: In gnotobiotic and conventional mice, mcr-1 significantly enhanced intestinal anchoring of E. coli but impaired their lethal effect. This improvement of intestinal fitness was associated with a downregulation of intestinal inflammatory markers and the preservation of intestinal microbiota composition. The mcr-1 gene mediated a cross-resistance to antimicrobial peptides secreted by the microbiota and intestinal epithelial cells (IECs), enhanced E. coli adhesion to IECs, and decreased the proinflammatory activity of both E. coli and its lipopolysaccharides. CONCLUSION: Overall, mcr-1 changed multiple facets of bacterial behaviour and appeared as a factor enhancing commensal lifestyle and persistence in the gut even in the absence of antibiotics. Video Abstract.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Animais , Camundongos , Escherichia coli/genética , Simbiose , Proteínas de Escherichia coli/genética , Farmacorresistência Bacteriana/genética , Antibacterianos/farmacologia , Infecções por Escherichia coli/microbiologia , Testes de Sensibilidade Microbiana
11.
Int J Mol Sci ; 24(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36674632

RESUMO

This study of a legume's rhizosphere in tripartite symbiosis focused on the relationships between the symbionts and less on the overall rhizosphere microbiome. We used an experimental model with different garden pea genotypes inoculated with AM fungi (Rhizophagus irregularis and with a mix of AM species) to study their influence on the population levels of main trophic groups of soil microorganisms as well as their structure and functional relationships in the rhizosphere microbial community. The experiments were carried out at two phenological cycles of the plants. Analyzes were performed according to classical methods: microbial population density defined as CUF/g a.d.s. and root colonization rate with AMF (%). We found a proven dominant effect of AMF on the densities of micromycetes and actinomycetes in the direction of reduction, suggesting antagonism, and on ammonifying, phosphate-solubilizing and free-living diazotrophic Azotobacter bacteria in the direction of stimulation, an indicator of mutualistic relationships. We determined that the genotype was decisive for the formation of populations of bacteria immobilizing mineral NH4+-N and bacteria Rhizobium. We reported significant two-way relationships between trophic groups related associated with soil nitrogen and phosphorus ions availability. The preserved proportions between trophic groups in the microbial communities were indicative of structural and functional stability.


Assuntos
Microbiota , Micorrizas , Micorrizas/genética , Ervilhas , Rizosfera , Raízes de Plantas/microbiologia , Fungos , Simbiose/genética , Microbiota/genética , Bactérias/genética , Solo/química , Genótipo , Microbiologia do Solo
12.
Int J Mol Sci ; 24(2)2023 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-36674741

RESUMO

SnRK1 protein kinase plays hub roles in plant carbon and nitrogen metabolism. However, the function of SnRK1 in legume nodulation and symbiotic nitrogen fixation is still elusive. In this study, we identified GmNodH, a putative sulfotransferase, as an interacting protein of GmSnRK1 by yeast two-hybrid screen. The qRT-PCR assays indicate that GmNodH gene is highly expressed in soybean roots and could be induced by rhizobial infection and nitrate stress. Fluorescence microscopic analyses showed that GmNodH was colocalized with GsSnRK1 on plasma membrane. The physical interaction between GmNodH and GmSnRK1 was further verified by using split-luciferase complementary assay and pull-down approaches. In vitro phosphorylation assay showed that GmSnRK1 could phosphorylate GmNodH at Ser193. To dissect the function and genetic relationship of GmSnRK1 and GmNodH in soybean, we co-expressed the wild-type and mutated GmSnRK1 and GmNodH genes in soybean hairy roots and found that co-expression of GmSnRK1/GmNodH genes significantly promoted soybean nodulation rates and the expression levels of nodulation-related GmNF5α and GmNSP1 genes. Taken together, this study provides the first biological evidence that GmSnRK1 may interact with and phosphorylate GmNodH to synergistically regulate soybean nodulation.


Assuntos
Nodulação , Soja , Nodulação/genética , Soja/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fixação de Nitrogênio/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Simbiose/genética , Regulação da Expressão Gênica de Plantas
13.
Proc Biol Sci ; 290(1990): 20222153, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36598018

RESUMO

In mutualism, hosts select symbionts via partner choice and preferentially direct more resources to symbionts that provide greater benefits via sanctions. At the initiation of symbiosis, prior to resource exchange, it is not known how the presence of multiple symbiont options (i.e. the symbiont social environment) impacts partner choice outcomes. Furthermore, little research addresses whether hosts primarily discriminate among symbionts via sanctions, partner choice or a combination. We inoculated the legume, Acmispon wrangelianus, with 28 pairs of fluorescently labelled Mesorhizobium strains that vary continuously in quality as nitrogen-fixing symbionts. We find that hosts exert robust partner choice, which enhances their fitness. This partner choice is conditional such that a strain's success in initiating nodules is impacted by other strains in the social environment. This social genetic effect is as important as a strain's own genotype in determining nodulation and has both transitive (consistent) and intransitive (idiosyncratic) effects on the probability that a symbiont will form a nodule. Furthermore, both absolute and conditional partner choice act in concert with sanctions, among and within nodules. Thus, multiple forms of host discrimination act as a series of sieves that optimize host benefits and select for costly symbiont cooperation in mixed symbiont populations.


Assuntos
Fabaceae , Simbiose/genética , Fixação de Nitrogênio , Genótipo , Nitrogênio
14.
Proc Biol Sci ; 290(1990): 20221909, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36629106

RESUMO

Linking local to regional ecological and evolutionary processes is key to understand the response of Earth's biodiversity to environmental changes. Here we integrate evolution and mutualistic coevolution in a model of metacommunity dynamics and use numerical simulations to understand how coevolution can shape species distribution and persistence in landscapes varying in space and time. Our simulations show that coevolution and species richness can synergistically shape distribution patterns by increasing colonization and reducing extinction of populations in metacommunities. Although conflicting selective pressures emerging from mutualisms may increase mismatches with the local environment and the rate of local extinctions, coevolution increases trait matching among mutualists at the landscape scale, counteracting local maladaptation and favouring colonization and range expansions. Our results show that by facilitating colonization, coevolution can also buffer the effects of environmental changes, preventing species extinctions and the collapse of metacommunities. Our findings reveal the mechanisms whereby coevolution can favour persistence under environmental changes and highlight that these positive effects are greater in more diverse systems that retain landscape connectivity.


Assuntos
Biodiversidade , Simbiose , Extinção Biológica , Fenótipo , Ecossistema
15.
Bioresour Technol ; 370: 128574, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36603749

RESUMO

In this study, the microalgae-bacteria symbiosis (ABS) system by co-culturing Chlorella sorokiniana with activated sludge was constructed for pollutants removal, and the according interaction mechanism was investigated. The results showed that the ABS system could almost completely remove ammonia nitrogen, and the removal efficiency of total nitrogen and total phosphorus could accordingly reach up to 65.3 % and 42.6 %. Brevundimonas greatly promoted microalgal biomass growth (maximum chlorophyll-a concentration of 9.4 mg/L), and microalgae contributed to the increase in the abundance of Dokdonella and Thermomonas in ABS system, thus facilitating nitrogen removal. The extended Derjaguin-Landau-Verwey-Overbeek theory indicated a repulsive potential barrier of 561.7 KT, while tryptophan-like proteins and tyrosine-like proteins were key extracellular polymeric substances for the formation of flocs by microalgae and activated sludge. These findings provide an in-depth understanding of interaction mechanism between microalgae and activated sludge for the removal of contaminants from wastewater.


Assuntos
Chlorella , Microalgas , Purificação da Água , Esgotos , Microalgas/metabolismo , Simbiose , Nutrientes , Bactérias , Nitrogênio/metabolismo , Purificação da Água/métodos , Fósforo/metabolismo , Biomassa
16.
Curr Biol ; 33(1): R22-R25, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36626858

RESUMO

Understanding the order and importance of events through which endosymbionts transition into cellular organelles (organellogenesis) is central to hypotheses about the origin of the eukaryotic cell. A new study on host-symbiont integration in a unicellular eukaryote reveals host-derived cell-division proteins that are targeted to the cell envelope of a bacterial endosymbiont and involved in its cell division.


Assuntos
Organelas , Simbiose , Bactérias , Eucariotos
17.
Immunity ; 56(1): 43-57.e10, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36630917

RESUMO

There is growing recognition that regionalization of bacterial colonization and immunity along the intestinal tract has an important role in health and disease. Yet, the mechanisms underlying intestinal regionalization and its dysregulation in disease are not well understood. This study found that regional epithelial expression of the transcription factor GATA4 controls bacterial colonization and inflammatory tissue immunity in the proximal small intestine by regulating retinol metabolism and luminal IgA. Furthermore, in mice without jejunal GATA4 expression, the commensal segmented filamentous bacteria promoted pathogenic inflammatory immune responses that disrupted barrier function and increased mortality upon Citrobacter rodentium infection. In celiac disease patients, low GATA4 expression was associated with metabolic alterations, mucosal Actinobacillus, and increased IL-17 immunity. Taken together, these results reveal broad impacts of GATA4-regulated intestinal regionalization on bacterial colonization and tissue immunity, highlighting an elaborate interdependence of intestinal metabolism, immunity, and microbiota in homeostasis and disease.


Assuntos
Infecções por Enterobacteriaceae , Mucosa Intestinal , Animais , Camundongos , Intestino Delgado , Simbiose , Imunidade nas Mucosas , Fator de Transcrição GATA4/metabolismo
18.
Sci Rep ; 13(1): 804, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36646812

RESUMO

Transport systems are crucial in many plant processes, including plant-microbe interactions. Nodule formation and function in legumes involve the expression and regulation of multiple transport proteins, and many are still uncharacterized, particularly for nitrogen transport. Amino acids originating from the nitrogen-fixing process are an essential form of nitrogen for legumes. This work evaluates the role of MtN21 (henceforth MtUMAMIT14), a putative transport system from the MtN21/EamA-like/UMAMIT family, in nodule formation and nitrogen fixation in Medicago truncatula. To dissect this transporter's role, we assessed the expression of MtUMAMIT14 using GUS staining, localized the corresponding protein in M. truncatula root and tobacco leaf cells, and investigated two independent MtUMAMIT14 mutant lines. Our results indicate that MtUMAMIT14 is localized in endosomal structures and is expressed in both the infection zone and interzone of nodules. Comparison of mutant and wild-type M. truncatula indicates MtUMAMIT14, the expression of which is dependent on the presence of NIN, DNF1, and DNF2, plays a role in nodule formation and nitrogen-fixation. While the function of the transporter is still unclear, our results connect root nodule nitrogen fixation in legumes with the UMAMIT family.


Assuntos
Medicago truncatula , Nódulos Radiculares de Plantas , Nódulos Radiculares de Plantas/genética , Nódulos Radiculares de Plantas/metabolismo , Medicago truncatula/genética , Medicago truncatula/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fixação de Nitrogênio/fisiologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Nitrogênio/metabolismo , Simbiose , Regulação da Expressão Gênica de Plantas
19.
Sci Rep ; 13(1): 907, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650168

RESUMO

Syntrophic cooperation among prokaryotes is ubiquitous and diverse. It relies on unilateral or mutual aid that may be both catalytic and metabolic in nature. Hypotheses of eukaryotic origins claim that mitochondrial endosymbiosis emerged from mutually beneficial syntrophy of archaeal and bacterial partners. However, there are no other examples of prokaryotic syntrophy leading to endosymbiosis. One potential reason is that when externalized products become public goods, they incite social conflict due to selfish mutants that may undermine any mutualistic interactions. To rigorously evaluate these arguments, here we construct a general mathematical framework of the ecology and evolution of different types of syntrophic partnerships. We do so both in a general microbial and in a eukaryogenetic context. Studying the case where partners cross-feed on each other's self-inhibiting waste, we show that cooperative partnerships will eventually dominate over selfish mutants. By contrast, systems where producers actively secrete enzymes that cross-facilitate their partners' resource consumption are not robust against cheaters over evolutionary time. We conclude that cross-facilitation is unlikely to provide an adequate syntrophic origin for endosymbiosis, but that cross-feeding mutualisms may indeed have played that role.


Assuntos
Evolução Biológica , Simbiose , Ecologia , Células Eucarióticas/metabolismo , Eucariotos
20.
Nat Ecol Evol ; 7(1): 143-154, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36593292

RESUMO

Species interactions drive evolution while evolution shapes these interactions. The resulting eco-evolutionary dynamics and their repeatability depend on how adaptive mutations available to community members affect fitness and ecologically relevant traits. However, the diversity of adaptive mutations is not well characterized, and we do not know how this diversity is affected by the ecological milieu. Here we use barcode lineage tracking to address this question in a community of yeast Saccharomyces cerevisiae and alga Chlamydomonas reinhardtii that have a net commensal relationship that results from a balance between competitive and mutualistic interactions. We find that yeast has access to many adaptive mutations with diverse ecological consequences, in particular those that increase and reduce the yields of both species. The presence of the alga does not change which mutations are adaptive in yeast (that is, there is no fitness trade-off for yeast between growing alone or with alga), but rather shifts selection to favour yeast mutants that increase the yields of both species and make the mutualism stronger. Thus, in the presence of the alga, adaptative mutations contending for fixation in yeast are more likely to enhance the mutualism, even though cooperativity is not directly favoured by natural selection in our system. Our results demonstrate that ecological interactions not only alter the trajectory of evolution but also dictate its repeatability; in particular, weak mutualisms can repeatably evolve to become stronger.


Assuntos
Evolução Biológica , Chlamydomonas reinhardtii , Microbiota , Saccharomyces cerevisiae , Simbiose , Microbiota/genética , Microbiota/fisiologia , Mutação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia , Simbiose/genética , Simbiose/fisiologia , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/fisiologia
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