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1.
Development ; 149(10)2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35502748

RESUMO

Adventitious roots (ARs) are an important type of plant root and display high phenotypic plasticity in response to different environmental stimuli. It is known that photoreceptors inhibit darkness-induced hypocotyl adventitious root (HAR) formation by directly stabilizing Aux/IAA proteins. In this study, we further report that phytochrome-interacting factors (PIFs) plays a central role in HAR initiation by simultaneously inducing the expression of genes involved in auxin biosynthesis, auxin transport and the transcriptional control of root primordium initiation. We found that, on the basis of their activity downstream of phytochrome, PIFs are required for darkness-induced HAR formation. Specifically, PIFs directly bind to the promoters of some genes involved in root formation, including auxin biosynthesis genes YUCCA2 (YUC2) and YUC6, the auxin influx carrier genes AUX1 and LAX3, and the transcription factors WOX5/7 and LBD16/29, to activate their expression. These findings reveal a previously uncharacterized transcriptional regulatory network underlying HAR formation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Hipocótilo/genética , Hipocótilo/metabolismo , Ácidos Indolacéticos/metabolismo , Fitocromo/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
2.
Plant Physiol ; 194(4): 2491-2510, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38039148

RESUMO

Passion fruit (Passiflora edulis) possesses a complex aroma and is widely grown in tropical and subtropical areas. Here, we conducted the de novo assembly, annotation, and comparison of PPF (P. edulis Sims) and YPF (P. edulis f. flavicarpa) reference genomes using PacBio, Illumina, and Hi-C technologies. Notably, we discovered evidence of recent whole-genome duplication events in P. edulis genomes. Comparative analysis revealed 7.6∼8.1 million single nucleotide polymorphisms, 1 million insertions/deletions, and over 142 Mb presence/absence variations among different P. edulis genomes. During the ripening of yellow passion fruit, metabolites related to flavor, aroma, and color were substantially accumulated or changed. Through joint analysis of genomic variations, differentially expressed genes, and accumulated metabolites, we explored candidate genes associated with flavor, aroma, and color distinctions. Flavonoid biosynthesis pathways, anthocyanin biosynthesis pathways, and related metabolites are pivotal factors affecting the coloration of passion fruit, and terpenoid metabolites accumulated more in PPF. Finally, by heterologous expression in yeast (Saccharomyces cerevisiae), we functionally characterized 12 terpene synthases. Our findings revealed that certain TPS homologs in both YPF and PPF varieties produce identical terpene products, while others yield distinct compounds or even lose their functionality. These discoveries revealed the genetic and metabolic basis of unique characteristics in aroma and flavor between the 2 passion fruit varieties. This study provides resources for better understanding the genome architecture and accelerating genetic improvement of passion fruits.


Assuntos
Frutas , Passiflora , Frutas/genética , Odorantes , Passiflora/genética , Passiflora/metabolismo , Multiômica , Terpenos/metabolismo
3.
Small ; 20(7): e2306178, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37800605

RESUMO

The ethanol oxidation reaction (EOR) is an attractive alternative to the sluggish oxygen evolution reaction in electrochemical hydrogen evolution cells. However, the development of high-performance bifunctional electrocatalysts for both EOR and hydrogen evolution reaction (HER) is a major challenge. Herein, the synthesis of Pd3 Pb@Pt core-shell nanocubes with controlled shell thickness by Pt-seeded epitaxial growth on intermetallic Pd3 Pb cores is reported. The lattice mismatch between the Pd3 Pb core and the Pt shell leads to the expansion of the Pt lattice. The synergistic effects between the tensile strain and the core-shell structures result in excellent electrocatalytic performance of Pd3 Pb@Pt catalysts for both EOR and HER. In particular, Pd3 Pb@Pt with three Pt atomic layers shows a mass activity of 8.60 A mg-1 Pd+Pt for ethanol upgrading to acetic acid and close to 100% of Faradic efficiency for HER. An EOR/HER electrolysis system is assembled using Pd3 Pb@Pt for both the anode and cathode, and it is shown that low cell voltage of 0.75 V is required to reach a current density of 10 mA cm-2 . The present work offers a promising strategy for the development of bifunctional catalysts for hybrid electrocatalytic reactions and beyond.

4.
Langmuir ; 40(17): 9012-9019, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38625688

RESUMO

Hydrate-based CO2 storage in the ocean is considered a potential method for mitigating the greenhouse effect. Numerous studies demonstrated that NaCl exhibited the dual effects of promotion and inhibition in the nucleation and growth processes of CO2 hydrate, whose mechanisms remain unclear. In this study, the effects of NaCl at various concentrations on the CO2 hydrate growth and crystal are investigated. The independent gradient model based on Hirshfeld partition, electrostatic potential, and binding energy is conducted to study the interaction between ions and water molecules. The motion trajectories of ions are observed at the molecular level to reflect the impact of ion motion on hydrate growth. The results show that the influence of NaCl on hydrate growth depends on a delicate balance of dual promotion-inhibition effects. NaCl can combine more water molecules and provide a transport channel of CO2 to promote hydrate growth at low concentrations. Meanwhile, the promoting effects shift toward inhibition with increasing NaCl concentrations. In a word, this paper proposes a novel mechanism for the dual promotion-inhibition effects of NaCl on hydrate growth, which is significant for further research on hydrate-based CO2 storage in the ocean.

5.
Langmuir ; 40(24): 12709-12720, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38843518

RESUMO

Great aqueous dispersibility, a large specific surface area, and high impermeability make graphene oxide (GO) the ideal candidate for a high-performance corrosion inhibitor. Numerous symmetrical modification methods have been reported to enhance the adsorption of GO on metal surfaces in various corrosive media. This work aims to investigate the enhancement and mechanism of unilateral hydrophobic modification on the corrosion inhibition performance of GO. In this study, amphiphilic Janus GO (JGO) was prepared by grafting hydrophobic alkyl chains on one side of GO, and its anticorrosion performance was evaluated via weight loss experiments and electrochemical tests. The results revealed that the corrosion inhibition efficiency for Q235 mild steel (MS) in a 1 M HCl aqueous solution of 25 ppm JGO (81.08%) was much higher than that of GO at the same concentration (22.12%). Furthermore, the Langmuir adsorption isotherm and computational study demonstrated that the synergistic effect of physical adsorption and chemical adsorption promoted the hydrophilic side of JGO close to the surface of the metal, and the dense protective layer was formed by the hydrophobic chains toward the corrosive medium, which effectively hindered the corrosion of MS by the acidic liquid. This study emphasizes the significant role of asymmetrically modified hydrophobic alkyl chains in improving the corrosion prevention performance of GO and provides a perspective for the structural design of GO-based corrosion inhibitors.

6.
Langmuir ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38932615

RESUMO

A novel polymeric ionic liquid (PDBA-IL-NH2) using imidazolium ionic liquids with short alkyl chains as monomers and two control ionic liquids (PDBA-IL-OH and PIL-NH2) were synthesized. Their inhibition properties and mechanisms were explored via surface analysis, weight loss tests, electrochemical studies, and adsorption isotherm analysis. The corrosion inhibition efficiency (CIE) of PDBA-IL-NH2 gradually increased with increasing concentration, and the largest efficiency was 94.67% at 100 ppm. At the same concentration (50 ppm), the corrosion inhibition abilities of inhibitors were in the order of PDBA-IL-NH2 > PDBA-IL-OH > PIL-NH2 > IL-NH2. Based on the experimental investigation, the synergistic effect of electrostatic interaction, protonation, and electron donor-acceptor interaction facilitated the intensive entanglement and coverage of PDBA-IL-NH2 with the reticulated form on the metal, and the generated densest films protected the metal from the corrosive media. Ultimately, the theoretical results of molecular dynamics simulations and quantum chemical study were in high agreement with the experimental data, which confirmed the proposed inhibition mechanisms on the microscopic scale. This study contributed valuable perspectives to the design of efficient and ecofriendly corrosion inhibitors.

7.
Eur Radiol ; 34(7): 4686-4696, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38133674

RESUMO

OBJECTIVES: To investigate the feasibility of non-contrast-enhanced MR angiography (NCE-MRA) in evaluating the morphology and blood supply of left gastric vein (LGV) in patients with gastroesophageal varices. METHODS: Between March 2021 and October 2022, patients with gastroesophageal varices and who underwent NCE-MRA were retrospectively reviewed. In order to evaluate the blood supply of LGV, superior mesenteric vein (SMV) and splenic vein (SV) were visualized separately by using inflow-sensitive inversion recovery sequence. Two radiologists independently assessed the image quality, determined the origination and the blood supply of LGV, and measured the diameter of LGV. The origination and diameter of LGV were compared between NCE-MRA and contrast-enhanced CT. Differences in blood supply were compared between LGVs with different originations. RESULTS: A total of 53 patients were enrolled in this study and the image quality was categorized as good or excellent in 52 patients. No significant differences were observed in visualizing the origination and the diameter of LGV between NCE-MRA and contrast-enhanced CT (p > .05). The blood supply of LGV was related to its origination (p < .001). Most LGVs with SV origination were supplied by SV. If LGV was originated from the portal vein (PV), about 70% of them were supplied by both SV and SMV. Compared with LGVs with SV origination, LGVs with PV origination showed more chance to receive blood from SMV (p < .001). CONCLUSION: Non-contrast-enhanced MR angiography appears to be a reliable technique in evaluating the morphology and blood supply of LGV in patients with gastroesophageal varices. CLINICAL RELEVANCE STATEMENT: Non-contrast-enhanced MR angiography provides valuable information for the management of gastroesophageal varices. Especially, it benefits patients with renal insufficiency. KEY POINTS: • Non-contrast-enhanced MR angiography using inflow-sensitive inversion recovery technique can be used for evaluating not only morphology as CT but also blood supply of left gastric vein. • The blood supply of left gastric vein is related to its origination and left gastric vein with portal vein origination shows more chance to receive blood from superior mesenteric vein.


Assuntos
Varizes Esofágicas e Gástricas , Estudos de Viabilidade , Angiografia por Ressonância Magnética , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Estudos Retrospectivos , Angiografia por Ressonância Magnética/métodos , Idoso , Adulto , Estômago/irrigação sanguínea , Estômago/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Veia Esplênica/diagnóstico por imagem , Veias Mesentéricas/diagnóstico por imagem , Meios de Contraste
8.
BMC Pediatr ; 24(1): 242, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580989

RESUMO

EPIDERMOLYSIS: Bullosa is a rare hereditary skin condition that causes blisters. Genes encoding structural proteins at or near the dermal-epidermal junction are mutated recessively or dominantly, and this is the primary cause of EB. Herein, two Chinese boys were diagnosed with the condition, each with a different variant in a gene that serves as a reference for EB genetic counseling. Skincare significantly impacted their prognosis and quality of life. CASE PRESENTATION: Two Chinese boys, with phenotypically normal parents, have been diagnosed with distinct blister symptoms, one with Dominant Dystrophic Epidermolysis Bullosa and the other with a severe form of Epidermolysis Bullosa Simplex. The first patient had a G-to-A variant in the COL7A1 allele, at nucleotide position 6163 which was named "G2055A". The proband is heterozygous for Dystrophic Epidermolysis Bullosa due to a COL7A1 allele with a glycine substitution at the triple helix domain. A similar variant has been discovered in his mother, indicating its potential transmission to future generations. Another patient had severe Epidermolysis Bullosa Simplex with a rare c.377T > A  variant resulting in substitution of amino acid p.Leu126Arg (NM_000526.5 (c.377T > G, p.Leu126Arg) in the Keratin 14 gene. In prior literature, Keratin 14 has been associated with an excellent prognosis. However, our patient with this infrequent variant tragically died from sepsis at 21 days old. There has been a reported occurrence of the variant only once. CONCLUSION: Our study reveals that Epidermolysis Bullosa patients with COL7A1 c.6163G > A and KRT14 c.377T>A variants have different clinical presentations, with dominant forms of Dystrophic EB having milder phenotypes than recessive ones. Thus, the better prognosis in the c.6163G > A patient. Furthermore, c.377T>A patient was more prone to infection than the patient with c.6163G>A gene variant. Genetic testing is crucial for identifying the specific variant responsible and improving treatment options.


Assuntos
Epidermólise Bolhosa Distrófica , Epidermólise Bolhosa Simples , Epidermólise Bolhosa , Humanos , Masculino , Colágeno , Colágeno Tipo VII/genética , Colágeno Tipo VII/metabolismo , Epidermólise Bolhosa/genética , Epidermólise Bolhosa Distrófica/diagnóstico , Epidermólise Bolhosa Distrófica/genética , Epidermólise Bolhosa Distrófica/metabolismo , Queratina-14/genética , Mutação , Qualidade de Vida
9.
Plant J ; 112(2): 535-548, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36062348

RESUMO

Benzylisoquinoline alkaloids (BIAs) are a class of plant secondary metabolites with great pharmacological value. Their biosynthetic pathways have been extensively elucidated in the species from the Ranunculales order, such as poppy and Coptis japonica, in which methylation events play central roles and are directly responsible for BIA chemodiversity. Here, we combined BIA quantitative profiling and transcriptomic analyses to identify novel BIA methyltransferases (MTs) from Liriodendron chinense, a basal angiosperm plant. We identified an N-methyltransferase (LcNMT1) and two O-methyltransferases (LcOMT1 and LcOMT3), and characterized their biochemical functions in vitro. LcNMT1 methylates (S)-coclaurine to produce mono- and dimethylated products. Mutagenesis experiments revealed that a single-residue alteration is sufficient to change its substrate selectivity. LcOMT1 methylates (S)-norcoclaurine at the C6 site and LcOMT3 methylates (S)-coclaurine at the C7 site, respectively. Two key residues of LcOMT3, A115 and T301, are identified as important contributors to its catalytic activity. Compared with Ranunculales-derived NMTs, Magnoliales-derived NMTs were less abundant and had narrower substrate specificity, indicating that NMT expansion has contributed substantially to BIA chemodiversity in angiosperms, particularly in Ranunculales species. In summary, we not only characterized three novel enzymes that could be useful in the biosynthetic production of valuable BIAs but also shed light on the molecular origin of BIAs during angiosperm evolution.


Assuntos
Alcaloides , Benzilisoquinolinas , Liriodendron , Magnoliopsida , Benzilisoquinolinas/metabolismo , Magnoliopsida/genética , Magnoliopsida/metabolismo , Metiltransferases/metabolismo , Liriodendron/metabolismo , Alcaloides/metabolismo
10.
J Magn Reson Imaging ; 58(2): 510-517, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36408884

RESUMO

BACKGROUND: Increasing evidence has indicated that the entire visual pathway from retina to visual cortex may be involved in dysthyroid optic neuropathy (DON) pathological mechanisms. PURPOSE: To explore the functional and morphological brain characteristics in DON and their relationship with ophthalmologic performance. STUDY TYPE: Retrospective. POPULATION: A total of 30 DON patients, 40 thyroid-associated ophthalmopathy (TAO) without DON patients and 21 healthy-controls (HCs). FIELD STRENGTH/SEQUENCE: A 3.0 T, 3D T1-weighted spoiled gradient-recalled echo and gradient-recalled echo-planar imaging. ASSESSMENT: Functional and structural alterations in brain regions were evaluated with fractional amplitude of low-frequency fluctuations, degree centrality (DC), and gray matter volume (GMV). Clinical activity score (CAS) is assessed across patients. STATISTICAL TEST: One-way analysis of variance with post hoc two sample t-tests (GRF-corrected, voxel level: P < 0.005, cluster level: P < 0.05) and correlation analysis (significance level: P < 0.05). RESULTS: Compared to HCs, DON patients had significantly decreased DC values in the bilateral BA17 and BA18 regions. Compared to the TAO group, DON patients had decreased GMV in the left anterior cingulate cortex, left middle frontal gyrus, left lingual gyrus, left parietal gyrus, right Rolandic operculum, left supplementary motor area, and right middle temporal gyrus. In addition, GMV in the right Rolandic operculum was significantly positively correlated with CAS (correlation coefficient: r = 0.448). DATA CONCLUSION: This study showed significant morphological and functional alterations in visual cortex and morphological alterations in partial default mode network regions of DON patients, which may provide insights into the mechanism of vision loss and may facilitate the diagnosis and treatment of DON. EVIDENCE LEVEL: 3. TECHNICAL EFFICACY: Stage 3.


Assuntos
Imageamento por Ressonância Magnética , Doenças do Nervo Óptico , Humanos , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem , Substância Cinzenta/patologia , Doenças do Nervo Óptico/diagnóstico por imagem , Doenças do Nervo Óptico/patologia
11.
J Magn Reson Imaging ; 57(3): 834-844, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35864716

RESUMO

BACKGROUND: The mechanism driving dysthyroid optic neuropathy (DON) is unclear. Diffusion-tensor imaging (DTI) allows for noninvasively assessing the microstructure of the entire visual pathway and may facilitate a better understanding of the mechanism of DON. PURPOSE: To assess microstructural changes of the whole visual pathway and to investigate the potential mechanism of trans-synaptic damage(TSD) pathogenesis in DON with DTI. STUDY TYPE: Cross-sectional. POPULATION: Sixty-four patients with bilateral thyroid-associated ophthalmopathy (TAO), 30 with and 34 without DON, and 30 age- and sex-matched healthy controls (HCs). FIELD STRENGTH/SEQUENCE: 3 T/DTI (A single-shot diffusion-weighted echo-planar imaging sequence). ASSESSMENT: Differences in DTI parameters including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) in each segment (optic nerve, tract, and radiation) of the entire visual pathway among the groups were compared. The parameters of visual evoked potentials (VEPs), visual field tests, and mean retinal nerve fiber layer (mRNFL) thickness on optical coherence tomography were also compared across patients. STATISTICAL TESTS: Student's t-test, chi-square test; ANOVA with post-hoc testing, interclass correlation coefficient, and correlation analysis. Significance level: P < 0.05. RESULTS: TAO patients with DON showed significantly reduced mRNFL thickness and abnormal VEPs. There was a tendency for gradually reduced FA and AD, and increased RD and MD from HCs, with non-DON to with DON in optic nerve and tract, statistically. For radiation, the RD and MD showed statistical increase, the AD and FA just showed numerical decrease (P = 0.119 and 0.059, respectively). For DON, the FA and MD of visual pathway segments showed correlations with abnormal VEPs. DATA CONCLUSION: DTI may be a useful tool for detecting microstructural changes in the entire visual pathway in DON. The changes in RNFL thickness and DTI parameters suggested TSD as a potential pathogenic mechanism of DON. EVIDENCE LEVEL: 4 Technical Efficacy: Stage 5.


Assuntos
Oftalmopatia de Graves , Doenças do Nervo Óptico , Humanos , Oftalmopatia de Graves/complicações , Oftalmopatia de Graves/diagnóstico por imagem , Estudos Transversais , Potenciais Evocados Visuais , Nervo Óptico/diagnóstico por imagem , Nervo Óptico/patologia , Doenças do Nervo Óptico/diagnóstico por imagem , Doenças do Nervo Óptico/complicações , Doenças do Nervo Óptico/patologia
12.
Langmuir ; 39(32): 11448-11458, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37535862

RESUMO

Nanoparticles (NPs) exhibit great potential to improve various properties of viscoelastic surfactant (VES) fracturing fluids in the development of low-permeability reservoirs. In the present study, the amphiphilic Janus NPs (JANPs) were fabricated via the Pickering emulsion method and employed to construct the novel JA12C (JANPs with dodecyl hydrophobic carbon chains)-assisted VES fracturing fluid (JAVES). The successful fabrication of JANPs was confirmed via Fourier transform infrared spectroscopy (FTIR) measurements and water contact angle tests. The rheology behavior of the VES fracturing fluid incorporating various SiO2 NPs including hydrophilic SiO2 NPs (HLNPs), JA8C (JANPs with octyl hydrophobic carbon chains), and JA12C was systematically investigated. It was revealed that the additional JA12C significantly improved the tolerance and proppant suspension properties. To explore the subsequent oil recovery performance of various gel breaking liquids, the formation wettability and the oil-water interfacial tension (IFT) were studied after the evaluation of breaking properties and formation damage properties of various fracturing fluids. The results suggested that the JAVES gel breaking liquid showed remarkable wettability alternation capability and moderate oil-water IFT reduction ability, which can partially reduce the impact on reservoir permeability. Moreover, the formation mechanism of the JAVES was proposed by molecular dynamics simulations at the molecular level, which was further visually verified via the cryo-TEM images. The improved viscoelasticity of developed the JAVES with moderate interfacial activity is advantageous to enhance subsequent oil recovery.

13.
Eur Radiol ; 33(11): 7981-7991, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37410107

RESUMO

OBJECTIVES: To investigate the brain functional alterations in dysthyroid optic neuropathy (DON) by evaluating spontaneous neural activity, using functional magnetic resonance imaging (fMRI) with regional homogeneity (ReHo), and its relationship with ophthalmologic performance. METHODS: Forty-seven patients with thyroid-associated ophthalmopathy (TAO; 20 with DON, 27 with non-DON) and 33 age-, sex-, and education-matched healthy controls (HCs) underwent fMRI. ReHo values were compared using one-way analysis of variance (ANOVA) with post hoc pairwise comparisons (voxel-level p < 0.01, Gaussian random field correction, cluster-level p < 0.05). Correlations between ReHo values and ophthalmological metrics were assessed for DONs, with Bonferroni correction for multiple comparisons (p < 0.004). ROC curves were applied to evaluate the diagnostic performance of ReHo metrics. RESULTS: ReHo values were significantly lower in the left insula and right superior temporal gyrus, and higher in the left posterior cingulate cortex (LPCC), of DON than of non-DON patients. ReHo values were also significantly lower in the right middle temporal, left insula, and left precentral gyrus in DON than in HCs. Meanwhile, ReHo values were higher in LPCC in non-DON than in HCs. ReHo values correlated with ophthalmic examinations to varying degrees in DON. For distinguishing DON, the ReHo values in LPCC showed optimal individually (AUC = 0.843), the combination of the ReHo in both the left insula and LPCC performed better (AUC = 0.915). CONCLUSION: Spontaneous brain activity differed between TAO with and without DON, which may reflect the underlying pathological mechanism of DON. The ReHo index can be considered a diagnostic biomarker. CLINICAL RELEVANCE STATEMENT: Spontaneous brain activity in DON differed from that in TAO without DON, which may reflect the underlying pathological mechanism of DON. The ReHo index can be considered a diagnostic biomarker for early detection of DON. KEY POINTS: • Dysthyroid optic neuropathy (DON) affects brain activity, which contributes in the understanding of its visual dysfunction. • Regional homogeneity values differ between thyroid-associated ophthalmopathy with and without DON in various brain regions. • Regional homogeneity values can be used as a biomarker in the differential diagnosis of DON.


Assuntos
Oftalmopatia de Graves , Doenças do Nervo Óptico , Humanos , Mapeamento Encefálico/métodos , Oftalmopatia de Graves/complicações , Oftalmopatia de Graves/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Biomarcadores
14.
Fish Shellfish Immunol ; 133: 108543, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36669601

RESUMO

The collectin subfamily member 11 (Colec11), plays an important role in innate immunity as a pattern recognition molecule. In the present study, a colec11 homolog was identified and characterised from Qihe crucian carp, namely, Ca-colec11. The full-length cDNA of Ca-colec11 was composed of 1129 bp, with a 99 bp 5'-untranslated region (UTR), 816 bp open reading frame (ORF) encoding a 271-aa protein and 214 bp 3'-UTR with a polyadenylation signal sequence (aataaa) and a poly(A) tail. The deduced amino acid sequence of Ca-Colec11 contained a si gnal peptide, collagen domain, neck region and carbohydrate-recognition domain (CRD), which had four conserved cysteine residues (Cys170-Cys256 and Cys242-Cys264) and an EPN/WND motif required for carbohydrate-binding specificity. Tissue expression profile analysis by quantitative real-time polymerase chain reaction (RT-qPCR) showed that Ca-colec11 was ubiquitously distributed in the tested tissues and highly expressed in the liver. The gene expression levels of Ca-colec11 were evidently up-regulated in the liver, spleen, kidney and head kidney after infection with A. hydrophila and S. aureus. The recombinant Ca-Colec11 (rCa-Colec11) purified from Escherichia coli BL21 (DE3) could agglutinate A. hydrophila and S. aureus, and it possessed haemagglutination activity against rabbit erythrocytes, which was inhibited by various carbohydrates, including d-Mannose, N-Acetyl-d-mannosamine, l-Fucose, d-Glucose, N-Acetyl-d-glucosamine, d-Galactose, LPS and PGN. Furthermore, rCa-Colec11 could inhibit the growth of A. hydrophila and S. aureus. These findings collectively demonstrated that Ca-Colec11, as a PRR, could play a role in the immune defence of Qihe crucian carp.


Assuntos
Carpas , Carpa Dourada , Animais , Coelhos , Carpas/genética , Carpas/metabolismo , Staphylococcus aureus/metabolismo , Aeromonas hydrophila/genética , Sequência de Bases , Proteínas de Peixes/química , Colectinas/genética , Carboidratos , Imunidade Inata/genética , Filogenia
15.
Ecotoxicol Environ Saf ; 262: 115313, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37556960

RESUMO

Dimethyl disulfide (DMDS) is a relatively new soil fumigant used in agro-industrial crop production to control soil-borne pests that damage crops and reduce yield. The emissions of DMDS after fumigation reduce soil concentrations thus reducing the risk of phytotoxicity to newly planted crops. However, the factors affecting the desorption of DMDS from soil are unclear. In our study, the desorption characteristics of DMDS from soil were measured in response to continuous ventilation. The degradation of DMDS in soil was examined by thermal incubation. The phytotoxic response of newly-planted cucumber (Cucumis sativus) seedlings to DMDS residues was measured by a sand culture experiment. The results showed DMDS desorption and degradation rates fit a first-order model; that 92% of the DMDS desorption occurred in the first hour after fumigant application; and that residue concentrations in the soil at the end of the ventilation period were unlikely to be phytotoxic to newly-planted cucumber seedlings. By the third day of ventilation, the average desorption rate (ADR) of DMDS in Wenshan soil was 4.0 and 3.6 times, respectively, faster than that in Shunyi and Suihua soils and the ADR of DMDS in soil decreased by 40.0% when the soil moisture content increased from 3% to 12% (wt/wt). Moreover, within one hour of ventilation, the ADR of DMDS in soil decreased by 20.1% when the soil bulk density increased from 1.1 to 1.3 g cm-3. The degradation of DMDS in soil, however, was mostly influenced by soil type and moisture content. A slow degradation rate resulted in a high initial desorption concentration of DMDS in soil. Our results indicated that DMDS desorption from soil in response to continuous ventilation was affected by the soil type, moisture content and bulk density. Rapid degradation of DMDS in soil will lower the risk of phytotoxic residues remaining in the soil and reduce emissions during the waiting period. Acceleration of emissions early in the waiting period by managing soil moisture content or increasing soil porosity may shorten the duration of emissions. Alternatively, soil extraction technology could be developed to recover and reduce fumigant emissions.

16.
Pestic Biochem Physiol ; 192: 105414, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37105623

RESUMO

The γ-aminobutyric acid receptors (GABARs) mediate fast inhibitory transmission in central nervous system of insects and are important targets of insecticides. An auxiliary subunit, Shisa7, was identified in mammals as a single-passing transmembrane protein. However, the homology gene(s) of Shisa in invertebrates has not been reported to date. In the present study, a homolog Shisa gene was identified from the two-spotted spider mite, Tetranychus urticae Koch. Its open reading frame had 927 base pairs and encoded 308 amino acid residues, which has a typical Shisa domain at 13th-181st amino acid residues. According to the phylogenetic tree, the invertebrate Shisa was categorized apart with those of vertebrate, and TuShisa showed closest relationship with the Shisa9 of velvet mite, Dinothrombium tinctorium (L.). In the electrophysiological assay with two-electrode voltage clamp, the GABA-activated TuRDL channel was functionally formed in the Africa clawed frog Xenopus laevis (Daudin) oocytes (EC50 = 53.34 µM). No GABA-activated current could be observed in TuShisa-expressed oocytes, whereas TuShisa could reduce the sensitivity of TuRDL/TuShisa (mass ratio of 1: 4) channel to GABA. The homology structural models of TuRDL and TuShisa were built by the SWISS-MODEL server, their interaction was predicted using Z-DOCK and three predicted hydrogen bonds and interface residues were analysed by PyMOL. Meanwhile, the key interface residues of TuShisa affected the stability of complex were calculated by Discovery Studio 2019. In conclusion, the TuShisa, as the first reported invertebrate Shisa, was explored and functionally examined as the GABARs auxiliary subunit. Our findings provide a basis for research of invertebrate Shisa.


Assuntos
Proteínas de Membrana , Tetranychidae , Animais , Aminoácidos/metabolismo , Inseticidas/metabolismo , Mamíferos/metabolismo , Filogenia , Receptores de GABA/química , Tetranychidae/genética , Tetranychidae/metabolismo
17.
Plant Dis ; 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37874285

RESUMO

Brachybotrys paridiformis Maxim. ex Oliv. (Boraginaceae) is a perennial medicinal plant and vegetable that is cultivated commercially in China. Anthracnose is a devastating disease of B. paridiformis, with annual production losses exceeding 33% based on our survey. In July 2021, anthracnose of B. paridiformis was observed on 2-year-old plants in Shenyang city, Northeast China, which is the most important region for B. paridiformis cultivation. Round or irregular-shaped black spots were exhibited on leaves, with the leaf edges most commonly infected. As the necrosis expanded, the leaves withered and dropped; young leaves were generally not infected (Fig. 1). More than 40% of the plants in a 21-ha sampling field were infected in 2021. Symptomatic leaves (n = 20) were collected and the diseased tissue was cut into small pieces, immersed in 1% NaOCl for 2 min, rinsed three times with sterile water, and placed on acidified potato dextrose agar (PDA) in Petri dishes. After a 3-day incubation in darkness at 25 °C, 18 suspected single-pure morphologically identical Colletotrichum isolates were obtained and sequenced. Isolate SQZ9 was randomly selected and identified. Colonies on PDA were initially white, but gradually became pale brownish with a reverse side that was pale yellowish to pinkish. Aerial mycelia were grayish-white, dense, and cottony, with microsclerotia detected on some aging mycelia. The detected single-celled conidia (11.65-17.25 × 4.25-6.15 µm; n = 50) were fusiform to cylindrical with obtuse to slightly rounded ends. Appressoria were ovoid to clavate and medium brown. Setae were not observed. The morphological characteristics were similar to those of Colletotrichum spp. (Prihastuti et al. 2009; Weir et al. 2012). Initial BLAST searches of the GenBank database revealed the SQZ9 rDNA internal transcribed spacer region (OP389109, 566 bp), glyceraldehyde-3-phosphate dehydrogenase (OP407730, 260 bp), chitin synthase (OP407731, 301 bp), calmodulin (OP407732, 712 bp), actin (OP407733, 282 bp), glutamine synthetase (OP407734, 909 bp), ß-tublin (OP407735, 498 bp), and superoxide dismutase (OP407736, 396 bp) sequences were respectively 99%-100% similar to the C. siamense type strain JX010278, JX010019, JX009709, GQ856775, GQ856730, JX010100, JX010410, and JX010332 sequences (Carbone & Kohn 1999; Moriwaki & Tsukiboshi 2009; Stephenson et al. 1997). The SQZ9 identity was confirmed by constructing a phylogenetic tree combining all loci, which grouped the isolate and the C. siamense type strain in the same clade (Fig. 2). For pathogenicity tests, 15 healthy 2-year-old plants (3 plants per pot) were spray-inoculated with SQZ9 conidial suspension (1 × 105 conidia/mL) at 2 mL per plant. Same number of plants sprayed with water were used as control. This experiment was repeated twice. All plants were covered with clear plastic bags for 72 h to maintain high humidity and then placed in a greenhouse (29 °C, natural light, and 85% relative humidity). After six days, the inoculated leaves exhibited symptoms that were similar to those observed in the field, but the controls were symptomless. The same fungus was recovered from inoculated symptomatic leaves, and its identity was confirmed by sequencing and a phylogenetic analysis. This is the first report of C. siamense causing anthracnose on B. paridiformis in China. Future studies should assess the effectiveness of chemical and biological control measures for managing this disease.

18.
Plant Dis ; 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37938908

RESUMO

Ligularia fischeri (Ledeb.) is a perennial herbal plant of Compositae that is cultivated commercially in China as a medicinal, ornamental, and edible plant. Leaf spots were observed in 2-year-old L. fischeri in Benxi County of northeast China, in August 2021. Irregular reddish brown spots ranging from 3 to 11 mm were observed on infected leaves, and each leaf had dozens of spots (Fig. 1). As the disease progressed, the diseased spots withered and the centers fell out, and multiple lesions merge into large diseased spots, causing leaf wilting. The roots and stem bases were not infected during the reproductive stage. More than 37% of the plants in a 18 ha field were infected in 2021. The ten diseased leaves were collected and cut into small (3-5 mm) pieces, which were surface-disinfested by immersing into 1% NaOCl for 2 min and rinsing with sterile distilled water three times. The leaf pieces were then placed on acidified potato dextrose agar (PDA) in petri plates and incubated in the dark at 25°C. Twenty isolates with the same morphological characteristics were obtained. Isolates were further purified by starting a new colony for each isolate from a single spore collected from water agar. Isolate TYTW7 was randomly selected for identification and pathogenicity testing. It grew rapidly and produced profuse aerial mycelia with a carmine red underside. The conidiophores had many fertile branches and formed an elongated stipe with a sphaeropedunculate vesicle at the tip. The one-septate conidia were cylindrical and almost straight with parallel walls and rounded ends. Their sizes ranged from 30.35 to 51.76 × 2.93 to 5.01 µm (n = 100) and the pathogens were initially identified as Calonectria sp. (Crous 2002; Crous et al. 2004; Lombard et al. 2015, 2016). Further confirmation of the identification was determined according to published method (Liu and Chen 2017; Shao and Li 2021). The partial gene regions including the translation elongation factor 1-alpha (GenBank accession no. OP290551), histone H3 (OP290552), calmodulin (OP290553) and ß-tubulin (OP290554) were obtained, and BLAST searches showed 99-100% homology with the ex-type culture CERC 8952 (MF527049, MF527065, MF527081 and MF527107) and phylogenetic analysis combining all loci revealed that the isolate TYTW7 and the type strain of Ca. montana clustered in one group (Fig. 2). Based on morphological characteristics and phylogenetic analysis, isolate TYTW7 was identified as Ca. Montana. Healthy 2-year-old plants were used for the pathogenicity test. A spore suspension (1×105 spores/mL water) was used to inoculate three host plants; sterile water was sprayed on the same number plants serving as a control. The experiment was repeated three times. All plants were incubated at 27±2°C (12h photoperiod) and were evaluated after seven days. The inoculated plants showed lesions on the leaf surface, similar to those in the field, and the control remained symptomless. The pathogens were successfully reisolated and identified by sequencing, and no pathogens were isolated from symptomless control plants. To our knowledge, this is the first report of Ca. montana causing L. fischeri leaf spot. The disease poses a threat to the production and more control strategies are needed on management options to minimize losses.

19.
Plant Dis ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38035781

RESUMO

Macleaya cordata (Willd.) R. Br. is a perennial herbaceous medicinal plant (Papaveraceae) commercially cultivated in China which has been studied for detumescence, detoxification, and insecticidal effect (Lin et al. 2018). In August 2021, anthracnose was observed in 2-year-old M. cordata plants in Benxi county, northeast China (41°45'48″N, 123°69'15″E). Dozens of irregular reddish-brown spots (3-11 mm) were observed on each diseased leaf. The lesions were covered with a layer of gray-white mycelia. As the disease progressed, the spots became necrosis and perforation or they would merged into large lesions, ultimately resulting in wilted leaves (Fig. 1). More than 33% of the plants in a 16-ha field were infected in 2021. The diseased leaves were collected and cut into 3-8 mm pieces, surface-disinfested by immersing them into 1% NaOCl for 2 min, and rinsed three times with sterile distilled water. They were then dried with sterilized absorbent paper, placed on PDA medium amended with chloramphenicol (40 mg/L), and incubated in darkness at 25°C with a 12-h photoperiod. Twenty isolates (BLH1 to 20) were obtained and purified using a single-spore method. Isolate BLH12 was identified and used for the pathogenicity test. Colonies were sparsely fluffy with smooth edges, and gradually became gray to pale orange from the initial white. The underside of the colonies was pale orange towards the center. Conidia were single-celled, cylindrical, and transparent with broadly blunt ends, measuring (15.13 ± 1.14) × (5.80 ± 0.60) µm (n=50). Appressoria were single-celled, brown-to-dark brown, usually elliptical or irregular, and sometimes lobed. Setae were not observed. The isolate was initially identified as Colletotrichum gloeosporioides complex (Prihastuti et al. 2009). The identification was confirmed as described previously (Weir et al. 2012). The rDNA internal transcribed spacer region (OP415560), the glyceraldehyde-3-phosphate dehydrogenase (OP433642), chitin synthase (OP433643), calmodulin (OP433644), actin (OP433645), glutamine synthetase (OP433646), ß-tubulin (OP433647), and superoxide dismutase (OP433648) gene sequences were obtained (Carbone & Kohn 1999; Weir et al. 2012), and BLAST searches revealed 99-100% homology with the type culture ICMP 18608 (JX010244, JX010044, JX009683, JX009443, JX009744, JX010078, JX010389, and JX010311). A phylogenetic analysis of combining all loci indicated BLH12 and the type strain of C. aenigma were clustered in one group (Fig. 2). Based on the basis of morphological characteristics and phylogenetic relationships, BLH12 was identified as C. aenigma. For the pathogenicity test, healthy 2-year-old plants were sprayed with a BLH12 spore suspension (1 × 105/mL). Control plants were sprayed with sterile water.There were three replicates (five plants each) per treatment. All plants were incubated at 25°C (12-h photoperiod and 86% relative humidity) and examined after 7 days. The experiment was repeated twice. The inoculated plants showed lesions on the leaf surface, similar to those in the field, whereas the control plants were asymptomatic. The pathogen was successfully reisolated and identified as the methods mentioned above. This fungus reportedly infects the leaves of many woody plants in China (Wang et al. 2020; Zhang et al. 2021). This is the first report of C. aenigma causing anthracnose on M. cordata, which will provide an guideline for developing effective field control practices for the disease.

20.
J Integr Plant Biol ; 65(5): 1344-1355, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36621865

RESUMO

The Gametophyte factor1 (Ga1) locus in maize confers unilateral cross-incompatibility (UCI), and it is controlled by both pollen and silk-specific determinants. Although the Ga1 locus has been reported for more than a century and is widely utilized in maize breeding programs, only the pollen-specific ZmGa1P has been shown to function as a male determinant; thus, the genomic structure of the Ga1 locus and all the determinants that control UCI at this locus have not yet been fully characterized. Here, we used map-based cloning to confirm the determinants of UCI at the Ga1 locus and maize pan-genome sequence data to characterize the genomic structure of the Ga1 locus. The Ga1 locus comprises one silk-expressed pectin methylesterase gene (PME) (ZmGa1F) and eight pollen-expressed PMEs (ZmGa1P and ZmGa1PL1-7). Knockout of ZmGa1F in Ga1/Ga1 lines leads to the complete loss of the female barrier function. The expression of individual ZmGa1PL genes in a ga1/ga1 background endows ga1 pollen with the ability to overcome the female barrier of the Ga1 locus. These findings, combined with genomic data and genetic analyses, indicate that the Ga1 locus is modulated by a single female determinant and multiple male determinants, which are tightly linked. The results of this study provide valuable insights into the genomic structure of the Ga2 and Tcb1 loci and will aid applications of these loci in maize breeding programs.


Assuntos
Zea mays , Células Germinativas Vegetais , Melhoramento Vegetal , Pólen/genética , Zea mays/genética , Zea mays/metabolismo
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