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1.
PLoS One ; 16(10): e0258235, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34679089

RESUMO

Carnivorous plants feed on animal prey, mainly insects, to get additional nutrients. This carnivorous syndrome is widely investigated and reported. In contrast, reports on herbivores feeding on carnivorous plants and related defenses of the plants under attack are rare. Here, we studied the interaction of a pitcher plant, Nepenthes x ventrata, with a generalist lepidopteran herbivore, Spodoptera littoralis, using a combination of LC/MS-based chemical analytics, choice and feeding assays. Chemical defenses in N. x ventrata leaves were analyzed upon S. littoralis feeding. A naphthoquinone, plumbagin, was identified in Nepenthes defense against herbivores and as the compound mainly responsible for the finding that S. littoralis larvae gained almost no weight when feeding on Nepenthes leaves. Plumbagin is constitutively present but further 3-fold increased upon long-term (> 1 day) feeding. Moreover, in parallel de novo induced trypsin protease inhibitor (TI) activity was identified. In contrast to TI activity, enhanced plumbagin levels were not phytohormone inducible, not even by defense-related jasmonates although upon herbivory their level increased more than 50-fold in the case of the bioactive jasmonic acid-isoleucine. We conclude that Nepenthes is efficiently protected against insect herbivores by naphthoquinones acting as phytoanticipins, which is supported by additional inducible defenses. The regulation of these defenses remains to be investigated.


Assuntos
Planta Carnívora/fisiologia , Herbivoria/fisiologia , Naftoquinonas/farmacologia , Compostos Fitoquímicos/farmacologia , Sarraceniaceae/fisiologia , Ácido Abscísico/farmacologia , Animais , Planta Carnívora/efeitos dos fármacos , Ciclopentanos/farmacologia , Dieta , Herbivoria/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Oxilipinas/farmacologia , Reguladores de Crescimento de Plantas/análise , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Inibidores de Proteases/farmacologia , Ácido Salicílico/farmacologia , Sarraceniaceae/efeitos dos fármacos , Spodoptera/efeitos dos fármacos , Spodoptera/fisiologia
2.
Plant Biol (Stuttg) ; 23(6): 1044-1050, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34532929

RESUMO

Studies addressing the impact of herbivory in carnivorous plants are scarce, despite loss of tissue being expected to be costly, as leaves are involved in both energy and nutrient acquisition. We evaluated the effect of simulated herbivory in a population of the carnivorous plant Pinguicula moranensis. We predicted an overall negative impact of herbivory by reducing growth, flowering probability and survivorship. Specifically, we expected that the increase in the negative effect should be related to the amount of leaf area removed. We performed simulated herbivory in plants growing in situ (2015) and ex situ (greenhouse, 2016) using a paper punch (herbivory ranging from 0 to 50%). In the ex-situ experiment, we also tested the effect of availability of resources by implementing a prey addition trial where half of the plants were supplemented with prey (one fruit fly per week). In both experiments, our hypothesis was not supported, as growth, flowering probability and survivorship were not influenced by herbivory treatments. Plants subjected to prey addition did not show higher performance than plants deprived of prey, contradicting our prediction that availability of resources could ameliorate the effect of herbivory. Overall, the lack of differences in performance between undamaged (control) and damaged plants indicate an unexpected short-term ability of P. moranensis to tolerate herbivory, even at high levels of damage.


Assuntos
Planta Carnívora , Herbivoria , Folhas de Planta
3.
Plant Physiol Biochem ; 166: 459-465, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34166972

RESUMO

Terrestrial carnivorous plants of genera Drosera, Dionaea and Nepenthes within the order Caryophyllales employ jasmonates for the induction of digestive processes in their traps. Here, we focused on two aquatic carnivorous plant genera with different trapping mechanism from distinct families and orders: Aldrovanda (Droseraceae, Caryophyllales) with snap-traps and Utricularia (Lentibulariaceae, Lamiales) with suction traps. Using phytohormone analyses and simple biotest, we asked whether the jasmonates are involved in the activation of carnivorous response similar to that known in traps of terrestrial genera of Droseraceae (Drosera, Dionaea). The results showed that Utricularia, in contrast with Aldrovanda, does not use jasmonates for activation of carnivorous response and is the second genus in Lamiales, which has not co-opted jasmonate signalling for botanical carnivory. On the other hand, the nLC-MS/MS analyses revealed that both genera secreted digestive fluid containing cysteine protease homologous to dionain although the mode of its regulation may differ. Whereas in Utricularia the cysteine protease is present constitutively in digestive fluid, it is induced by prey and exogenous application of jasmonic acid in Aldrovanda.


Assuntos
Droseraceae , Lamiales , Planta Carnívora , Ciclopentanos , Oxilipinas , Espectrometria de Massas em Tandem
4.
Int J Mol Sci ; 22(9)2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-34063704

RESUMO

Carnivorous plants are exemplary natural sources of secondary metabolites with biological activity. However, the therapeutic antimicrobial potential of these compounds is limited due to intrinsic resistance of selected bacterial pathogens, among which Pseudomonas aeruginosa represents an extreme example. The objective of the study was to overcome the intrinsic resistance of P. aeruginosa by combining silver nanoparticles (AgNPs) with secondary metabolites from selected carnivorous plant species. We employed the broth microdilution method, the checkerboard titration technique and comprehensive phytochemical analyses to define interactions between nanoparticles and active compounds from carnivorous plants. It has been confirmed that P. aeruginosa is resistant to a broad range of secondary metabolites from carnivorous plants, i.e., naphthoquinones, flavonoids, phenolic acids (MBC = 512 µg mL-1) and only weakly sensitive to their mixtures, i.e., extracts and extracts' fractions. However, it was shown that the antimicrobial activity of extracts and fractions with a significant level of naphthoquinone (plumbagin) was significantly enhanced by AgNPs. Our studies clearly demonstrated a crucial role of naphthoquinones in AgNPs and extract interaction, as well as depicted the potential of AgNPs to restore the bactericidal activity of naphthoquinones towards P. aeruginosa. Our findings indicate the significant potential of nanoparticles to modulate the activity of selected secondary metabolites and revisit their antimicrobial potential towards human pathogenic bacteria.


Assuntos
Planta Carnívora/química , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Antibacterianos/efeitos adversos , Antibacterianos/química , Farmacorresistência Bacteriana/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Naftoquinonas/efeitos adversos , Naftoquinonas/química , Naftoquinonas/farmacologia , Extratos Vegetais/química , Pseudomonas aeruginosa/patogenicidade , Metabolismo Secundário/efeitos dos fármacos , Prata/química , Espectrofotometria Ultravioleta
5.
Proc Biol Sci ; 288(1951): 20210771, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34036802

RESUMO

Similar to animals, plants have evolved mechanisms for elastic energy storage and release to power and control rapid motion, yet both groups have been largely studied in isolation. This is exacerbated by the lack of consistent terminology and conceptual frameworks describing elastically powered motion in both groups. Iconic examples of fast movements can be found in carnivorous plants, which have become important models to study biomechanics, developmental processes, evolution and ecology. Trapping structures and processes vary considerably between different carnivorous plant groups. Using snap traps, suction traps and springboard-pitfall traps as examples, we illustrate how traps mix and match various mechanisms to power, trigger and actuate motions that contribute to prey capture, retention and digestion. We highlight a fundamental trade-off between energetic investment and movement control and discuss it in a functional-ecological context.


Assuntos
Planta Carnívora , Movimento , Animais , Fenômenos Biomecânicos , Movimento (Física) , Plantas
6.
Acta Biomater ; 128: 357-369, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33862281

RESUMO

Nepenthes pitcher plants grow in nutrient-poor soils and produce large pitfall traps to obtain additional nutrients from animal prey. Previous research has shown that the digestive secretion in N. rafflesiana is a sticky viscoelastic fluid that retains insects much more effectively than water, even after significant dilution. Although the retention of prey is known to depend on the fluid's physical properties, the details of how the fluid interacts with insect cuticle and how its sticky nature affects struggling insects are unclear. In this study, we investigated the mechanisms behind the efficient prey retention in N. rafflesiana pitcher fluid. By measuring the attractive forces on insect body parts moved in and out of test fluids, we show that it costs insects more energy to free themselves from pitcher fluid than from water. Moreover, both the maximum force and the energy required for retraction increased after the first contact with the pitcher fluid. We found that insects sink more easily into pitcher fluid than water and, accordingly, the surface tension of N. rafflesiana pitcher fluid was lower than that of water (60.2 vs. 72.3 mN/m). By analysing the pitcher fluid's wetting behaviour, we demonstrate that it strongly resists dewetting from all surfaces tested, leaving behind residual films and filaments that can facilitate re-wetting. This inhibition of dewetting may be a further consequence of the fluid's viscoelastic nature and likely represents a key mechanism underlying prey retention in Nepenthes pitcher plants. STATEMENT OF SIGNIFICANCE: Carnivorous Nepenthes pitcher plants secrete sticky viscoelastic fluids that prevent insects from escaping after falling into the pitcher. What physical mechanisms are responsible for the fluid's retentive function? First, insects sink and drown more readily in N. rafflesiana pitcher fluid due to its reduced surface tension. Second, once within the fluid, our force measurements show that it costs more energy to separate insects from pitcher fluid than from water. Third, the fluid strongly resists dewetting, making it harder for insects to extract themselves and covering their cuticle with residues that facilitate re-wetting. Such striking inhibition of dewetting may represent a previously unrecognised mechanism of prey retention by Nepenthes. Pitcher fluid fulfils a well-defined biological function and may serve as a model for studying the mechanics of complex fluids.


Assuntos
Planta Carnívora , Insetos , Animais , Compostos Orgânicos
7.
Elife ; 102021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33724187

RESUMO

In response to touch, some carnivorous plants such as the Venus flytrap have evolved spectacular movements to capture animals for nutrient acquisition. However, the molecules that confer this sensitivity remain unknown. We used comparative transcriptomics to show that expression of three genes encoding homologs of the MscS-Like (MSL) and OSCA/TMEM63 family of mechanosensitive ion channels are localized to touch-sensitive trigger hairs of Venus flytrap. We focus here on the candidate with the most enriched expression in trigger hairs, the MSL homolog FLYCATCHER1 (FLYC1). We show that FLYC1 transcripts are localized to mechanosensory cells within the trigger hair, transfecting FLYC1 induces chloride-permeable stretch-activated currents in naïve cells, and transcripts coding for FLYC1 homologs are expressed in touch-sensing cells of Cape sundew, a related carnivorous plant of the Droseraceae family. Our data suggest that the mechanism of prey recognition in carnivorous Droseraceae evolved by co-opting ancestral mechanosensitive ion channels to sense touch.


Assuntos
Planta Carnívora/genética , Droseraceae/genética , Canais Iônicos/genética , Proteínas de Plantas/genética , Tato , Animais , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Planta Carnívora/metabolismo , Droseraceae/metabolismo , Genes de Plantas , Canais Iônicos/metabolismo , Transporte de Íons/genética , Proteínas de Plantas/metabolismo , Transcriptoma
8.
Plant Physiol Biochem ; 161: 113-121, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33581619

RESUMO

The carnivorous pitcher plants of the genus Nepenthes usually attract, capture and digest arthropod prey to obtain mineral nutrients. But few members of the genus have evolved specialized nutrient sequestration strategies to acquire nitrogen from the faeces and urine of mutualistic mammals, which they attract. Because the plants obtain significant amounts of nitrogen in a more available form, we hypothesized that they have relaxed the production of digestive enzymes. If so, species that digest mammal faeces should show fewer digestive enzymes than closely related species that rely on arthropods. We tested this hypothesis by comparing digestive enzymes in 1) Nepenthes hemsleyana, whose pitchers serve as roosts for the mutualistic woolly bat Kerivoula hardwickii, which also defecate inside the pitchers, and 2) the close relative Nepenthes rafflesiana, a typical arthropod capturing species. To investigate the dynamics of aspartic proteases (nepenthesin I and II) and type III and IV chitinases in both species, we conducted qPCR, western blotting, mass spectrometry, and enzyme activity measurements. We found that mRNA in pitcher tissue and enzyme abundance in the digestive fluid is upregulated in both species in response to faeces and insect feeding. Contrary to our initial hypothesis, the final nepenthesin proteolytic activity in the digestive fluid is higher in response to faeces addition than to insect prey irrespective of Nepenthes species. This indicates that faeces can mimic arthropod prey triggering the production of digestive enzymes and N. hemsleyana retained capacity for production of them.


Assuntos
Planta Carnívora , Magnoliopsida , Animais , Nitrogênio , Nutrientes , Compostos Orgânicos , Simbiose
9.
J Nat Prod ; 84(4): 964-971, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33631073

RESUMO

Phytochemical profiling was undertaken on the crude extracts of Drosera magna to determine the nature of the chemical constituents present. In total, three new flavonol diglycosides (1-3), one new flavan-3-ol glycoside (4), and 12 previously reported compounds of the flavonol (5, 9), flavan-3-ol (15), flavanone (8), 1,4-napthoquinone (6, 7, 13, 14), 2,3-dehydroxynapthalene-1,4-dione (10-12), and phenolic acid (16) structure classes were isolated and identified. Compounds 1-9, 13, 17, and 18 were assessed for antimicrobial activity, with compounds 6, 7, 8, and 9 showing significant activity. Compounds 1, 2, and 6 were also evaluated for anthelmintic activity against larval forms of Hemonchus contortus, with compound 6 being active.


Assuntos
Anti-Helmínticos/farmacologia , Anti-Infecciosos/farmacologia , Drosera/química , Flavonóis/farmacologia , Glicosídeos/farmacologia , Animais , Anti-Helmínticos/isolamento & purificação , Anti-Infecciosos/isolamento & purificação , Planta Carnívora/química , Flavonoides , Flavonóis/isolamento & purificação , Glicosídeos/isolamento & purificação , Haemonchus/efeitos dos fármacos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química , Raízes de Plantas/química , Austrália Ocidental
10.
Sci Rep ; 11(1): 1438, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446898

RESUMO

Upon stimulation, plants elicit electrical signals that can travel within a cellular network analogous to the animal nervous system. It is well-known that in the human brain, voltage changes in certain regions result from concerted electrical activity which, in the form of action potentials (APs), travels within nerve-cell arrays. Electro- and magnetophysiological techniques like electroencephalography, magnetoencephalography, and magnetic resonance imaging are used to record this activity and to diagnose disorders. Here we demonstrate that APs in a multicellular plant system produce measurable magnetic fields. Using atomic optically pumped magnetometers, biomagnetism associated with electrical activity in the carnivorous Venus flytrap, Dionaea muscipula, was recorded. Action potentials were induced by heat stimulation and detected both electrically and magnetically. Furthermore, the thermal properties of ion channels underlying the AP were studied. Beyond proof of principle, our findings pave the way to understanding the molecular basis of biomagnetism in living plants. In the future, magnetometry may be used to study long-distance electrical signaling in a variety of plant species, and to develop noninvasive diagnostics of plant stress and disease.


Assuntos
Potenciais de Ação/fisiologia , Planta Carnívora/fisiologia , Droseraceae/fisiologia , Transdução de Sinais/fisiologia
11.
J Chem Ecol ; 47(1): 73-86, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33417071

RESUMO

Most carnivorous plants show a conspicuous separation between flowers and leaf-traps, which has been interpreted as an adaptive response to minimize pollinator-prey conflicts which will reduce fitness. Here, we used the carnivorous subshrub Drosophyllum lusitanicum (Drosophyllaceae) to explore if and how carnivorous plants with minimal physical separation of flower and trap avoid or reduce a likely conflict of pollinator and prey. We carried out an extensive field survey in the Aljibe Mountains, at the European side of the Strait of Gibraltar, of pollinating and prey insects of D. lusitanicum. We also performed a detailed analysis of flower and leaf volatile and semi-volatile organic compounds (VOCs and SVOCs, respectively) by direct thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) to ascertain whether this species shows different VOC/SVOC profiles in flowers and leaf-traps that might attract pollinators and prey, respectively. Our results show a low overlap between pollinator and prey groups as well as clear differences in the relative abundance of VOCs and SVOCs between flowers and leaf-traps. Coleopterans and hymenopterans were the most represented groups of floral visitors, whereas dipterans were the most diverse group of prey insects. Regarding VOCs and SVOCs, while aldehydes and carboxylic acids presented higher relative contents in leaf-traps, alkanes and plumbagin were the main VOC/SVOC compounds detected in flowers. We conclude that D. lusitanicum, despite its minimal flower-trap separation, does not seem to present a marked pollinator-prey conflict. Differences in the VOCs and SVOCs produced by flowers and leaf-traps may help explain the conspicuous differences between pollinator and prey guilds.


Assuntos
Planta Carnívora/química , Insetos , Polinização , Compostos Orgânicos Voláteis/análise , Animais , Planta Carnívora/fisiologia , Flores/química , Folhas de Planta/química , Mucilagem Vegetal/química
12.
Protoplasma ; 258(1): 71-85, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32918205

RESUMO

Aldrovanda vesiculosa (Droseraceae) is a rare aquatic carnivorous plant, distributed in Europe, Asia, Africa, and Australia. Aldrovanda populations can flower prolifically under favourable conditions, but seed set is very limited. We studied the structure of Aldrovanda pollen collected from flowers in different developmental stages (opened and non-opened anthers) from both European and Australian populations to elucidate pollination traits and the basis of poor seed set on the basis of microscopic observation of pollen and anther structure. Microscopic analyses of Aldrovanda pollen showed that this plant has pollen arranged in tetrads like other species in the Droseraceae family. In hydrated pollen, cytoplasmic protrusions originate from pores located along the equatorial wall of monads, and can develop into pollen tubes. Interestingly, pollen development from microspores occurs in open anthers, suggesting a delay of the developmental stages. In addition, pollen development displays altered sperm cell formation and precocious pollen germination. Precocious germination may characterize recalcitrant pollen, which naturally do not undergo dehydration before anthesis and remain partially hydrated, particularly in aquatic and wetland plants. These alterations of male gametophyte development could affect fertilization processes, and be the reason for the low reproductive capability of Aldrovanda observed both in the field and in cultures. Generally, reduced pollen longevity and very quick germination are considered an adaptation to aquatic or wet environments.


Assuntos
Planta Carnívora/química , Droseraceae/química , Células Germinativas Vegetais/química , Pólen
13.
Sci Rep ; 10(1): 17482, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060701

RESUMO

In nutrient-poor habitats, carnivorous plants have developed novel feeding strategies based on the capture and digestion of prey and the assimilation of prey-derived nutrients by specialized traps. The Nepenthes genus, comprising nearly 160 species, presents a remarkable pitcher-shaped trap, leading to great interest among biologists, but the species of this genus are listed as threatened. In this work, we developed a protocol for reproducing Nepenthes mirabilis through shoot regeneration from calli. The cultivation of stem segments of N. mirabilis on MS medium containing thidiazuron induced organogenic calli after 10 weeks. Subcultured calli exposed to 6-benzylaminopurine showed shoot regeneration in 3 weeks with considerable yields (143 shoots/g of calli). Excised shoots transferred to medium with indole-3-butyric acid allowed rooting in 4 weeks, and rooted plantlets had a 100% survival rate. Based on this method, we also developed an Agrobacterium-mediated genetic transformation protocol using calli as explants and ipt as a positive method of selection. Twelve weeks post infection, regenerated shoots were observed at the surface of calli. Their transgenic status was confirmed by PCR and RT-PCR. In conclusion, this study provides an efficient method for regenerating Nepenthes and the first protocol for its stable genetic transformation, a new tool for studying carnivory.


Assuntos
Planta Carnívora/crescimento & desenvolvimento , Planta Carnívora/genética , Caryophyllales/crescimento & desenvolvimento , Caryophyllales/genética , Regeneração , Agrobacterium/genética , Compostos de Benzil/química , Biotecnologia , Indóis/química , Compostos de Fenilureia/química , Brotos de Planta/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Purinas/química , Tiadiazóis/química , Técnicas de Cultura de Tecidos , Transformação Genética
14.
BMC Res Notes ; 13(1): 426, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32912303

RESUMO

OBJECTIVE: Plant carnivory is distributed across the tree of life and has evolved at least six times independently, but sequenced and annotated nuclear genomes of carnivorous plants are currently lacking. We have sequenced and structurally annotated the nuclear genome of the carnivorous Roridula gorgonias and that of a non-carnivorous relative, Madeira's lily-of-the-valley-tree, Clethra arborea, both within the Ericales. This data adds an important resource to study the evolutionary genetics of plant carnivory across angiosperm lineages and also for functional and systematic aspects of plants within the Ericales. RESULTS: Our assemblies have total lengths of 284 Mbp (R. gorgonias) and 511 Mbp (C. arborea) and show high BUSCO scores of 84.2% and 89.5%, respectively. We used their predicted genes together with publicly available data from other Ericales' genomes and transcriptomes to assemble a phylogenomic data set for the inference of a species tree. However, groups of orthologs showed a marked absence of species represented by a transcriptome. We discuss possible reasons and caution against combining predicted genes from genome- and transriptome-based assemblies.


Assuntos
Clethraceae , Ericales , Magnoliopsida , Planta Carnívora , Carnivoridade , Genoma de Planta/genética , Filogenia
15.
J Microsc ; 280(2): 86-103, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32844427

RESUMO

Up-to-date imaging approaches were used to address the spatiotemporal organisation of the endomembrane system in secretory cells of Dionaea muscipula. Different 'slice and view' methodologies were performed on resin-embedded samples to finally achieve a 3D reconstruction of the cell architecture, using ultrastructural tomography, array tomography, serial block face-scanning electron microscopy (SBF-SEM), correlation, and volume rendering at the light microscopy level. Observations of cryo-fixed samples by high-pressure freezing revealed changes of the endomembrane system that occur after trap activation and prey digestion. They provide evidence for an original strategy that adapts the secretory machinery to a specific and unique case of stimulated exocytosis in plant cells. A first secretion peak is part of a rapid response to deliver digestive fluids to the cell surface, which delivers the needed stock of digestive materials 'on site'. The second peak of activity could then be associated with the reconstruction of the Golgi apparatus (GA), endoplasmic reticulum (ER) and vacuolar machinery, in order to prepare for a subsequent round of prey capture. Tubular continuum between ER and Golgi stacks observed on ZIO-impregnated tissues may correspond to an efficient transfer mechanism for lipids and/or proteins, especially for use in rapidly resetting the molecular GA machinery. The occurrence of one vacuolar continuum may permit continuous adjustment of cell homeostasy. The subcellular features of the secretory cells of Dionaea muscipula outline key innovations in the organisation of plant cell compartmentalisation that are used to cope with specific cell needs such as the full use of the GA as a protein factory, and the ability to create protein reservoirs in the periplasmic space. Shape-derived forces of the pleiomorphic vacuole may act as signals to accompany the sorting and entering flows of the cell.


Assuntos
Planta Carnívora/fisiologia , Planta Carnívora/ultraestrutura , Droseraceae/fisiologia , Droseraceae/ultraestrutura , Membranas Intracelulares/ultraestrutura , Tomografia com Microscopia Eletrônica , Retículo Endoplasmático/ultraestrutura , Exocitose , Processamento de Imagem Assistida por Computador , Microscopia Eletrônica de Varredura , Vesículas Secretórias/ultraestrutura , Tomografia , Vacúolos/ultraestrutura
16.
Int J Mol Sci ; 21(14)2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32708125

RESUMO

Carnivorous plants from the Lentibulariaceae form a variety of standard and novel vegetative organs and survive unfavorable environmental conditions. Within Genlisea, only G. tuberosa, from the Brazilian Cerrado, formed tubers, while Utricularia menziesii is the only member of the genus to form seasonally dormant tubers. We aimed to examine and compare the tuber structure of two taxonomically and phylogenetically divergent terrestrial carnivorous plants: Genlisea tuberosa and Utricularia menziesii. Additionally, we analyzed tubers of U. mannii. We constructed phylogenetic trees using chloroplast genes matK/trnK and rbcL and used studied characters for ancestral state reconstruction. All examined species contained mainly starch as histologically observable reserves. The ancestral state reconstruction showed that specialized organs such as turions evolved once and tubers at least 12 times from stolons in Lentibulariaceae. Different from other clades, tubers probably evolved from thick stolons for sect. Orchidioides and both structures are primarily water storage structures. In contrast to species from section Orchidioides, G. tuberosa, U. menziesii and U. mannii form starchy tubers. In G. tuberosa and U. menziesii, underground tubers provide a perennating bud bank that protects the species in their fire-prone and seasonally desiccating environments.


Assuntos
Planta Carnívora/anatomia & histologia , Planta Carnívora/genética , Cloroplastos/genética , Lamiales/genética , Tubérculos/anatomia & histologia , Estresse Fisiológico/fisiologia , Planta Carnívora/citologia , Planta Carnívora/ultraestrutura , Lamiales/anatomia & histologia , Lamiales/citologia , Lamiales/ultraestrutura , Microscopia Eletrônica de Varredura , Filogenia , Tubérculos/citologia , Tubérculos/genética , Tubérculos/ultraestrutura , Amido/metabolismo , Estresse Fisiológico/genética , Água/metabolismo
17.
Biomolecules ; 10(7)2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32709016

RESUMO

The Droserasins, aspartic proteases from the carnivorous plant Drosera capensis, contain a 100-residue plant-specific insert (PSI) that is post-translationally cleaved and independently acts as an antimicrobial peptide. PSIs are of interest not only for their inhibition of microbial growth, but also because they modify the size of lipid vesicles and strongly interact with biological membranes. PSIs may therefore be useful for modulating lipid systems in NMR studies of membrane proteins. Here we present the expression and biophysical characterization of the Droserasin 1 PSI (D1 PSI.) This peptide is monomeric in solution and maintains its primarily α -helical secondary structure over a wide range of temperatures and pH values, even under conditions where its three disulfide bonds are reduced. Vesicle fusion assays indicate that the D1 PSI strongly interacts with bacterial and fungal lipids at pH 5 and lower, consistent with the physiological pH of D. capensis mucilage. It binds lipids with a variety of head groups, highlighting its versatility as a potential stabilizer for lipid nanodiscs. Solid-state NMR spectra collected at a field strength of 36 T, using a unique series-connected hybrid magnet, indicate that the peptide is folded and strongly bound to the membrane. Molecular dynamics simulations indicate that the peptide is stable as either a monomer or a dimer in a lipid bilayer. Both the monomer and the dimer allow the passage of water through the membrane, albeit at different rates.


Assuntos
Planta Carnívora/metabolismo , Drosera/metabolismo , Bicamadas Lipídicas/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Planta Carnívora/química , Membrana Celular/metabolismo , Drosera/química , Fusão de Membrana , Simulação de Dinâmica Molecular , Proteínas Citotóxicas Formadoras de Poros/análise , Conformação Proteica em alfa-Hélice , Multimerização Proteica
18.
Integr Comp Biol ; 60(4): 852-863, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32658970

RESUMO

Suction feeding has evolved independently in two highly disparate animal and plant systems, aquatic vertebrates and carnivorous bladderworts. We review the suction performance of animal and plant suction feeders to explore biomechanical performance limits for aquatic feeders based on morphology and kinematics, in the context of current knowledge of suction feeding. While vertebrates have the greatest diversity and size range of suction feeders, bladderworts are the smallest and fastest known suction feeders. Body size has profound effects on aquatic organismal function, including suction feeding, particularly in the intermediate flow regime that tiny organisms can experience. A minority of tiny organisms suction feed, consistent with model predictions that generating effective suction flow is less energetically efficient and also requires more flow-rate specific power at small size. Although the speed of suction flows generally increases with body and gape size, some specialized tiny plant and animal predators generate suction flows greater than those of suction feeders 100 times larger. Bladderworts generate rapid flow via high-energy and high-power elastic recoil and suction feed for nutrients (relying on photosynthesis for energy). Small animals may be limited by available muscle energy and power, although mouth protrusion can offset the performance cost of not generating high suction pressure. We hypothesize that both the high energetic costs and high power requirements of generating rapid suction flow shape the biomechanics of small suction feeders, and that plants and animals have arrived at different solutions due in part to their different energy budgets.


Assuntos
Planta Carnívora , Comportamento Alimentar , Animais , Larva , Sucção , Vertebrados
19.
Curr Biol ; 30(12): 2312-2320.e5, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32413308

RESUMO

Most plants grow and develop by taking up nutrients from the soil while continuously under threat from foraging animals. Carnivorous plants have turned the tables by capturing and consuming nutrient-rich animal prey, enabling them to thrive in nutrient-poor soil. To better understand the evolution of botanical carnivory, we compared the draft genome of the Venus flytrap (Dionaea muscipula) with that of its aquatic sister, the waterwheel plant Aldrovanda vesiculosa, and the sundew Drosera spatulata. We identified an early whole-genome duplication in the family as source for carnivory-associated genes. Recruitment of genes to the trap from the root especially was a major mechanism in the evolution of carnivory, supported by family-specific duplications. Still, these genomes belong to the gene poorest land plants sequenced thus far, suggesting reduction of selective pressure on different processes, including non-carnivorous nutrient acquisition. Our results show how non-carnivorous plants evolved into the most skillful green hunters on the planet.


Assuntos
Evolução Biológica , Planta Carnívora/genética , Droseraceae/genética , Genoma de Planta
20.
Microscopy (Oxf) ; 69(4): 214-226, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32328650

RESUMO

The aquatic carnivorous plant Aldrovanda vesiculosa L. is critically endangered worldwide; its peculiar lifestyle raises many questions and poses problems both intriguing on their own and relevant to conservation. While establishing a culture system for its propagation and restoring its natural habitat in Hozoji pond in Saitama, Japan, we conducted ultrastructural observations to examine the various aspects of Aldrovanda's way of life. Electron microscopic observation in combination with cryo-techniques produced novel information which could not be obtained by other methods. Some of the results are: phosphorous is stored in petiole cells of turions during winter; mucilaginous guides are provided for pollen tubes in parietal placental ovaries; storage of potassium in the vicinity of the midrib of carnivorous leaves may contribute to the rapid closing of the carnivorous leaves; dynamic sequential changes of the ultrastructure of digestive glands are involved in the synthesis and secretion of digestive enzymes, including protease and acid phosphatase. These results should contribute significantly to our understanding of Aldrovanda and the detailed mechanisms of its life.


Assuntos
Planta Carnívora/fisiologia , Planta Carnívora/ultraestrutura , Droseraceae/fisiologia , Droseraceae/ultraestrutura , Microscopia Eletrônica/métodos , Planta Carnívora/anatomia & histologia , Microscopia Crioeletrônica/métodos , Droseraceae/anatomia & histologia , Japão
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