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1.
J Org Chem ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38917459

RESUMEN

An efficient synergistic trityl cation ([Ph3C][B(C6F5)4])/triflic anhydride (Tf2O) catalyzed alkylation of phenols with alcohols is reported. Benefiting from the formation of the triflate in situ, cheap and readily available active alcohols can be used as the alkylating reagents, and the reaction proceeds under mild reaction conditions with a broad substrate scope. This protocol enables the synthesis of ortho-selective phenols and 2,4,6-trisubstitued phenols containing three different alkyl groups. tert-Amyl triflate was synthesized, and mechanistic studies support a triflate-mediated alkylation process.

2.
Proc Natl Acad Sci U S A ; 117(40): 24813-24824, 2020 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-32963097

RESUMEN

Thousands of Down syndrome cell adhesion molecule (Dscam1) isoforms and ∼60 clustered protocadhrein (cPcdh) proteins are required for establishing neural circuits in insects and vertebrates, respectively. The strict homophilic specificity exhibited by these proteins has been extensively studied and is thought to be critical for their function in neuronal self-avoidance. In contrast, significantly less is known about the Dscam1-related family of ∼100 shortened Dscam (sDscam) proteins in Chelicerata. We report that Chelicerata sDscamα and some sDscamß protein trans interactions are strictly homophilic, and that the trans interaction is meditated via the first Ig domain through an antiparallel interface. Additionally, different sDscam isoforms interact promiscuously in cis via membrane proximate fibronectin-type III domains. We report that cell-cell interactions depend on the combined identity of all sDscam isoforms expressed. A single mismatched sDscam isoform can interfere with the interactions of cells that otherwise express an identical set of isoforms. Thus, our data support a model by which sDscam association in cis and trans generates a vast repertoire of combinatorial homophilic recognition specificities. We propose that in Chelicerata, sDscam combinatorial specificity is sufficient to provide each neuron with a unique identity for self-nonself discrimination. Surprisingly, while sDscams are related to Drosophila Dscam1, our results mirror the findings reported for the structurally unrelated vertebrate cPcdh. Thus, our findings suggest a remarkable example of convergent evolution for the process of neuronal self-avoidance and provide insight into the basic principles and evolution of metazoan self-avoidance and self-nonself discrimination.


Asunto(s)
Proteínas de Artrópodos/metabolismo , Artrópodos/metabolismo , Animales , Proteínas de Artrópodos/genética , Artrópodos/clasificación , Artrópodos/genética , Moléculas de Adhesión Celular/química , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Comunicación Celular , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Neuronas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
3.
Plant Dis ; 2022 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-35263156

RESUMEN

Eragrostis japonica (Thunb.) Trin, a kind of grass weeds in paddy rice fields, has recently been developing rapidly as the most harmful weed for rice production in addition to Echinochloa crusgalli and Leptochloa chinensis in partial areas of Anhui, Jiangsu, and Zhejiang provinces (Zhou et al.). In September 2019, inflated sori in the ovaries of E. japonica were identified in fields in Chuzhou County, Anhui Province. The disease incidence was approximately 50% at the survey site. Smut sori were in some spikelets of infected inflorescence destroying the inner most floral organs. Sori were ovoid and initially covered with a thin peridium (Figure 1). The sori busted after maturation, and the black powdery spores spread to the plant and soil. The sori were crushed using the sterilized tweezers. The black powdery spores were suspended with sterilized water and spread onto potato dextrose agar (PDA) medium. Spores were covered with spines, and the shape of spores varied from globose to ovoid. Scanning electron microscope was used to observe the morphology of spores. The spores were 7.5-12.3 µm × 5.8-11.8 µm (n=50). The surface of spores was covered with spines, and dense verruca were identified between the spines (Figure 2). For molecular identification, the primers ITS1/ITS4 and GAPDH-F/R were employed to amplify the rDNA region. The resulting sequences from the studied material were submitted to Genbank (MW819938 and MZ508441). BLASTn analysis revealed that ITS sequence shared 99% similarity with EF040584 (719/728) the ITS sequence from type specimen of Ustilago planetella. Based on the above results, the pathogen was identified as Ustilago planetella (Vánky, 2007). To verify the Koch's postulates, a pathogenicity test was performed by infiltrating the inflorescence with microspore suspensions of the strain SMZF-2 (1×106 spores/mL) when the E. japonica flowers for 30 minutes. The plants were inoculated in a moist chamber (with a relative humidity >80%) with a 12-h light cycle at 28℃. Inflated sori were observed after inoculated for 2 weeks, and U. planetella was isolated and identified with the methods described above. No sori were observed in the water-inoculated control plants. U. planetella had been reported to infect Eragrostis japonica in Thailand (Vánky, 2007). To our knowledge, this is the first report of U. planetella causing Smut on E. japonica (Thunb.) Trin in central region of China. The current study may help solve the negative effect of E. japonica in paddy rice production via using U. planetella in the future.

4.
J Org Chem ; 86(23): 17445-17452, 2021 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-34747599

RESUMEN

A palladium-catalyzed base-free decarbonylative borylation of aryl anhydrides has been developed. Catalyst system consisting of Pd(OAc)2/dppb enables readily available aryl anhydrides to be employed as electrophiles for the synthesis of versatile arylboronate esters via O-C(O) bond activation and decarbonylation. This method is characterized by an excellent functional group tolerance and broad substrate scope, using bench stable aryl anhydrides as aryl electrophiles in C-B bond formation. Mechanistic studies and functionalization of late-stage pharmaceutical molecules are disclosed.


Asunto(s)
Anhídridos , Paladio , Catálisis , Ésteres
5.
World J Surg Oncol ; 19(1): 182, 2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34154596

RESUMEN

BACKGROUND: The prognosis of pancreatic cancer (PC) is extremely poor, and most patients with metastatic PC still receive palliative care. Here, we report the efficacy and safety of FOLFIRINOX (oxaliplatin, irinotecan, leucovorin, 5-fluorouracil) in the treatment of metastatic PC. METHODS: We searched PubMed, Web of Science, EBSCO, and Cochrane library databases for articles that described efficacy and safety of FOLFIRINOX in patients with metastatic PC, from January 1996 to July 2020. The primary outcomes targeted included overall survival (OS) and progression-free survival (PFS). RESULTS: We found that FOLFIRINOX could directly improve OS rate of patients with metastatic PC (HR 0.76, 95% Cl 0.67-0.86, p<0.001) but had no benefit on PFS. Results from subgroup analyses showed that FOLFIRINOX had superior benefits than monochemotherapy (HR 0.59, 95% Cl 0.52-0.67, p<0.001), followed by FOLFIRINOX versus combination chemotherapy (HR 0.76, 95% Cl 0.61-0.95, p<0.001). The result of FOLFIRINOX versus nab-paclitaxel + gemcitabine had no benefit (HR 0.91, 95% Cl 0.82-1.02, p>0.05). The main adverse events (AEs) targeted hematological toxicity and the gastrointestinal system, and included febrile neutropenia, a reduction in white blood cells and appetite, as well as diarrhea. CONCLUSION: These findings indicated that FOLFIRINOX has potential benefits for the prognosis of patients with metastatic PC. Furthermore, there is no difference between the regimen of FOLFIRINOX and nab-paclitaxel + gemcitabine in this study. The application of FOLFIRINOX should be according to the actual situation of the patients and the experience of the doctors.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Pancreáticas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Fluorouracilo/uso terapéutico , Humanos , Irinotecán , Leucovorina/uso terapéutico , Oxaliplatino/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Pronóstico
6.
BMC Genomics ; 18(1): 953, 2017 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-29212446

RESUMEN

BACKGROUND: Asia minor bluegrass (Polypogon fugax, P. fugax), a weed that is both distributed across China and associated with winter crops, has evolved resistance to acetyl-CoA carboxylase (ACCase) herbicides, but the resistance mechanism remains unclear. The goal of this study was to analyze the transcriptome between resistant and sensitive populations of P. fugax at the flowering stage. RESULTS: Populations resistant and susceptible to clodinafop-propargyl showed distinct transcriptome profiles. A total of 206,041 unigenes were identified; 165,901 unique sequences were annotated using BLASTX alignment databases. Among them, 5904 unigenes were classified into 58 transcription factor families. Nine families were related to the regulation of plant growth and development and to stress responses. Twelve unigenes were differentially expressed between the clodinafop-propargyl-sensitive and clodinafop-propargyl-resistant populations at the early flowering stage; among those unigenes, three belonged to the ABI3VP1, BHLH, and GRAS families, while the remaining nine belonged to the MADS family. Compared with the clodinafop-propargyl-sensitive plants, the resistant plants exhibited different expression pattern of these 12 unigenes. CONCLUSION: This study identified differentially expressed unigenes related to ACCase-resistant P. fugax and thus provides a genomic resource for understanding the molecular basis of early flowering.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Resistencia a los Herbicidas/genética , Herbicidas/farmacología , Magnoliopsida/genética , Proteínas de Plantas/genética , Poa/genética , Acetil-CoA Carboxilasa/genética , Regulación de la Expresión Génica de las Plantas , Poa/efectos de los fármacos
7.
Pestic Biochem Physiol ; 124: 93-6, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26453236

RESUMEN

American sloughgrass [Beckmannia syzigachne (Steud.) Fernald] is a problematic annual grass weed in winter wheat fields of China, which causes great loss of wheat yield. Repeated use of acetyl-CoA carboxylase (ACCase)-inhibiting herbicides during the last two decades to control this weed has been selected for resistance in American sloughgrass in Jiangsu province. In this study, whole-plant dose-response assays were conducted to investigate the level of resistance in four resistant American sloughgrass populations (LY, JH, BYJ and BYP) to four ACCase-inhibiting herbicides belonging to aryloxyphenoxypropionates, cyclohexanediones, and phenylpyrazolines groups under greenhouse conditions. Based on resistance factor (RF), three populations, LY, BYJ and BYP, were highly resistant to fenoxaprop-P-ethyl, clodinafop propargyl, sethoxydim and pinoxaden. JH plants exhibited resistance to fenoxaprop-P-ethyl and clodinafop propargyl, but showed much lower RF values for sethoxydim and pinoxaden. Molecular analysis of resistance revealed that resistance in all the four populations was target site-based. Results confirmed that substitutions of Ile-1781-Leu, Ile-2041-Asn and Asp-2078-Gly, respectively, in LY, JH and BYJ/BYP, are responsible for diverse sensitivity to different ACCase-inhibiting herbicides in these populations. The substitution at position 1781 had been reported, while it is the first report of Ile-2041-Asn and Asp-2078-Gly mutations that corresponded to resistance in American sloughgrass.


Asunto(s)
Acetil-CoA Carboxilasa/genética , Herbicidas/toxicidad , Poaceae/efectos de los fármacos , China , Ciclohexanonas/toxicidad , Resistencia a los Herbicidas/genética , Compuestos Heterocíclicos con 2 Anillos/toxicidad , Mutación/genética , Poaceae/genética
8.
J Am Chem Soc ; 136(16): 5908-11, 2014 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-24712517

RESUMEN

The formation of catenated systems can be simplified greatly if one or more rings are generated via self-assembly. Herein we exploit the orthogonality of coordination-driven self-assembly and crown-ether host-guest complexation to obtain a [4]molecular necklace and a [7]molecular necklace based on a well-developed recognition motif of 1,2-bis(pyridinium)ethane/dibenzo[24]crown-8. By adapting the bis(pyridinium) motif into the backbone of a donor building block, the resulting semirigid dipyridyl species can serve both as a structural element in the formation of metallacycles and as a site for subsequent host-guest chemistry. The pseudolinear nature of the donor precursor lends itself to the formation of triangular and hexagonal central metallacycles based on the complementary acceptor unit used. This exemplary system organizes up to 18 molecules from three unique species in solution to afford a single supramolecular ensemble.

9.
Pestic Biochem Physiol ; 108: 16-20, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24485310

RESUMEN

Asia minor bluegrass (Polypogon fugax) is a common annual grass weed of winter crops distributed across China. We conducted a study on the resistance level and the mechanism of resistance to ACCase-inhibiting herbicides in a P. fugax population from China. Whole-plant dose-response experiments in greenhouse showed that the resistant P. fugax population was 1991, 364, 269, 157, and 8-fold resistant to clodinafop-propargyl, fluazifop-p-butyl, haloxyfop-R-methyl, quizalofop-p-ethyl and fenoxaprop-p-ethyl relative to the reference susceptible population, which was susceptible to all the five AOPP herbicides. Much lower R/S values of 3.5, 2.4 and 3.5, respectively, were detected for clethodim, sethoxydim and pinoxaden. Molecular analysis of resistance confirmed that the Ile2041 to Asn mutation in the resistant population conferred resistance to AOPP herbicides, but not to CHD and DEN herbicides. This is the first report of a target site mutation that corresponded to resistance to AOPP herbicides in P. fugax. Proper resistance management practices are necessary to prevent ACCase-inhibiting herbicides from becoming ineffective over wide areas.


Asunto(s)
Acetil-CoA Carboxilasa/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Resistencia a los Herbicidas , Herbicidas/farmacología , Proteínas de Plantas/antagonistas & inhibidores , Poa/efectos de los fármacos , Acetil-CoA Carboxilasa/genética , Acetil-CoA Carboxilasa/metabolismo , Secuencia de Aminoácidos , China , Datos de Secuencia Molecular , Mutación , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poa/enzimología , Poa/genética
10.
Ophthalmol Ther ; 13(7): 1993-2008, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38822193

RESUMEN

INTRODUCTION: This study investigates how surgery for pituitary adenoma (PA) affects the visual pathway, examining changes in the retina, blood vessel density, and nerve function. Since PAs often impair vision as a result of their location near visual structures, this research is key to understanding and improving vision recovery after surgery. METHODS: Our study is based on a retrospective analysis of the historical data of 28 patients diagnosed with pituitary adenomas. We conducted assessments by reviewing preoperative and postoperative imaging records. These included optical coherence tomography (OCT) for retinal structure analysis, diffusion tensor imaging (DTI) for neural transmission evaluation, and optical coherence tomography angiography for assessing blood vessel density. These tools allowed for a detailed understanding of the structural and functional changes within the visual pathway following PA surgery. RESULTS: OCT findings show postoperative changes in the eye: thinning in average and nasal circumpapillary retinal nerve fiber layer, thickening in macular central 1 mm inner plexus layer, ganglion cell complex, and nasal retinal nerve fiber layer. DTI reveals increased fractional anisotropy (FA) in the left optic chiasm and posterior optic nerve, decreased mid-segment optic nerve FA, and increased apparent diffusion coefficient (ADC) in the right optic chiasm and nerve segments. Early postoperative reduction in radial peripapillary capillaries plexus density is noted. Preoperative ganglion cell layer (GCL) thickness correlates with postoperative visual radiation FA and ADC values, especially in the inferior quadrant. A negative correlation exists between preoperative GCL thickness and postoperative visual field mean defect values, particularly on the temporal side and superior inner ring. All changes are statistically significant (P < 0.05). CONCLUSIONS: The study finds that surgery for PA has varied effects on vision. Early post surgery, there are changes in the retina and nerve signals. Macular GCL thickness before surgery might predict early visual recovery, influencing future research and treatment for vision issues related to PA.

11.
Sci Total Environ ; 904: 166587, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37659543

RESUMEN

Developing microcapsules (MCs) delivery systems can effectively mitigate toxicological risk of highly active/toxic pesticides; whereas the controlled release functions also limiting their practical effectiveness. Therefore, designing a precise regulating strategy to balance the toxicity and bioactivity of MCs is urgently needed. Here, we prepared a series of pyraclostrobin-loaded MCs with different wall materials, particle sizes, core density and shell compactness using interfacial polymerization. The results showed that the MCs released more slowly in water with increasing particle sizes and capsule compactness, and they sunk more quickly with the increasing particle sizes and core density. Additionally, MCs with slower release speed was always accompanied with lower acute toxicity levels to zebrafish. When the release dynamics slowed down to the threshold dose on demand for disease control, facilitating settlement of MCs can further reduce toxicity within spatial and temporal dimensions. The poor accumulation of MCs with larger particle sizes or dense shell in gills was closely related to their efficient detoxification. Importantly, seven of the MCs samples possessed superior selectivity between bio-performance in controlling rice blast and toxicological hazard to fish compared to commercial formulations. The results provide a comprehensive guidance for developing an efficient and safe pesticide delivery system.


Asunto(s)
Plaguicidas , Pez Cebra , Animales , Cápsulas , Estrobilurinas , Plaguicidas/toxicidad
12.
Pest Manag Sci ; 79(4): 1528-1537, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36527683

RESUMEN

BACKGROUND: We have previously demonstrated that an aldo-keto reductase (AKR) from Echinochloa colona (EcAKR4-1) can metabolize glyphosate and confers glyphosate resistance. This study aims to investigate if the EcAKR4-1 orthologs from Lolium rigidum also play a role in glyphosate resistance in non-target-site based, glyphosate-resistant (R) L. rigidum populations from Western Australia. RESULTS: The full-length L. rigidum AKR gene (LrAKR4C10) orthologous to EcAKR4-1, together with a distinct LrAKR1, were cloned from plants of a glyphosate-susceptible (S) (VLR1) and three glyphosate R L. rigidum populations (WALR50, WALR60 and WALR70). Reverse transcription quantitative polymerase chain reaction (RT-qPCR) results showed that basal expression levels of the two LrAKR genes did not differ between the R and S populations, but their expression was significantly induced by glyphosate (up to 4.3-fold) or 2,4-D treatment (up to 3.4-fold) in R populations. Escherichia coli cells transformed respectively with LrAKR4C10 and LrAKR1 were more tolerant to glyphosate. Rice (Oryza sativa) seedlings overexpressing each of the two LrAKR gene survived glyphosate rates that were lethal to the green fluorescence protein (GFP) control plants. Structural modeling predicts a similar way of glyphosate binding and detoxification by LrAKR4C10 and EcAKR4-1, but an alternative way of glyphosate binding by LrAKR1. Relatively lower capacity of the two LrAKRs in conferring glyphosate resistance than the known EcAKR4-1 was discussed in relation to structural interaction. CONCLUSION: Glyphosate-induced higher expression of the two LrAKR genes in L. rigidum populations contributes to a moderate level of glyphosate resistance likely through enhanced glyphosate metabolism. The herbicide 2,4-D can also induce the LrAKR expression, indicating the potential antagonistic effect of 2,4-D to glyphosate. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Herbicidas , Lolium , Aldo-Ceto Reductasas/metabolismo , Resistencia a los Herbicidas/genética , Herbicidas/farmacología , Ácido 2,4-Diclorofenoxiacético/farmacología , Glifosato
13.
J Agric Food Chem ; 71(24): 9302-9313, 2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37170102

RESUMEN

A wild radish population (R) has been recently confirmed to be cross-resistant to 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides without previous exposure to these herbicides. This cross-resistance is endowed by enhanced metabolism. Our study identified one 2-oxoglutarate/Fe(II)-dependent dioxygenase gene (Rr2ODD1) and two P450 genes (RrCYP704C1 and RrCYP709B1), which were significantly more highly expressed in R versus susceptible (S) plants. Gene functional characterization using Arabidopsis transformation showed that overexpression of RrCYP709B1 conferred a modest level of resistance to mesotrione. Ultra-performance liquid chromatography-tandem mass spectrometry analysis showed that tissue mesotrione levels in RrCYP709B1 transgenic Arabidopsis plants were significantly lower than that in the wild type. In addition, overexpression of Rr2ODD1 or RrCYP704C1 in Arabidopsis endowed resistance to tembotrione and isoxaflutole. Structural modeling indicated that mesotrione can bind to CYP709B1 and be easily hydroxylated to form 4-OH-mesotrione. Although each gene confers a modest level of resistance, overexpression of the multiple herbicide-metabolizing genes could contribute to HPPD-inhibiting herbicide resistance in this wild radish population.


Asunto(s)
4-Hidroxifenilpiruvato Dioxigenasa , Arabidopsis , Herbicidas , Raphanus , Herbicidas/química , 4-Hidroxifenilpiruvato Dioxigenasa/genética , 4-Hidroxifenilpiruvato Dioxigenasa/metabolismo , Raphanus/genética , Raphanus/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo
14.
Front Public Health ; 10: 982171, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36249245

RESUMEN

Background: Effective isolation and early treatment of coronavirus disease 2019 (COVID-19) relies on rapid, accurate, and straightforward diagnostic tools. In response to the rapidly increasing number of cases, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assays for multiple target genes have become widely available in the market. Methods: In total, 236 COVID-19 patients with positive results in both RT-qPCR and rapid antigen diagnosis (Ag-RDT) were enrolled in the study. The cycle threshold (Ct) was compared with different onset times and target genes. Comparison between groups was evaluated with the Kruskal-Wallis test and Dunn test. The correlation between target genes was analyzed by Spearman. Results: In samples of Ct ≤ 21, Ct was different for the nucleocapsid (N), open reading frame 1ab (ORF1ab), and envelope (E) genes (P < 0.05). Mild COVID-19 patients within 7 days of onset accounted for 67.80% of all enrolled patients. At the above stage, all target genes reached the trough of Ct, and N genes showed lower values than the other target genes. The Ct of the ORF1ab and N gene in asymptomatic patients differed from those of mild patients within 7 days and more than 14 days of onset. The kits used in the study showed strong consistency among target genes, with all correlation coefficients >0.870. Conclusion: RT-qPCR confirmed that the N gene performed well in Ct ≤ 21 and samples within 7 days of onset. Ag-RDT was discriminatory for patients within 7 days of onset. This study facilitated early identification and control of COVID-19 prevalence among patients.


Asunto(s)
COVID-19 , Ácidos Nucleicos , COVID-19/diagnóstico , Humanos , Ácidos Polimetacrílicos , SARS-CoV-2/genética , Sensibilidad y Especificidad
15.
Sci Adv ; 8(4): eabm1763, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35080968

RESUMEN

Drosophila melanogaster Dscam1 encodes 38,016 isoforms via mutually exclusive splicing; however, the regulatory mechanism behind this is not fully understood. Here, we found a set of hidden RNA secondary structures that balance the stochastic choice of Dscam1 splice variants (designated balancer RNA secondary structures). In vivo mutational analyses revealed the dual function of these balancer interactions in driving the stochastic choice of splice variants, through enhancement of the inclusion of distal exon 6s by cooperating with docking site-selector pairing to form a stronger multidomain pre-mRNA structure and through simultaneous repression of the inclusion of proximal exon 6s by antagonizing their docking site-selector pairings. Thus, we provide an elegant molecular model based on competition and cooperation between two sets of docking site-selector and balancer pairings, which counteracts the "first-come, first-served" principle. Our findings provide conceptual and mechanistic insight into the dynamics and functions of long-range RNA secondary structures.

16.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 4): o873-4, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21754151

RESUMEN

The title compound, C(26)H(23)F(2)NO(3), was synthesized by the reaction of 2-(4-fluoro-benzyl-idene)-4-methyl-3-oxo-N-phenyl-penta-namide and 4-fluoro-benzaldehyde. The dihedral angles between the mean plane through the pyrrolidine ring (nearly planar; maximum deviation of 0.145 Šfor the C atom bearing the hydroxy group) with the phenyl and benzene rings are 37.22 (7), 51.88 (7) and 87.64 (9)°, respectively. The pyyolidine ring is near coplaner, with max offset of 0.145 A for C19 atom.\uff09 In the crystal, mol-ecules are linked by pairs of O-H⋯O hydrogen bonds into inversion dimers, which are further assembled into chains parallel to the b axis by weak C-H⋯O hydrogen bonds.

17.
Funct Plant Biol ; 48(8): 793-801, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33820601

RESUMEN

Herbicides are the major tool for controlling large populations of yield depleting weeds. However, over-reliance on herbicides has resulted in weed adaptation and herbicide resistance. In recent years, early flowering weed species related to herbicide resistance is emerging, which may cause seed loss before crop harvest, creating a new problem for non-chemical weed management. In this study, a homologue gene of AGAMOUS sub-family (referred to as PfAG5) of the MADS-box family was cloned from plants of an early flowering Polypogon fugax Nees ex Steud. population resistant to the ACCase inhibitor herbicide (clodinafop-propargyl). The PfAG5 gene was functionally characterised in Arabidopsis thaliana L. Overexpression of the PfAG5 gene in Arabidopsis resulted in early flowering, abnormal flowers (e.g. small petals), short plants and reduced seed set, compared with the wild type. The expression of the PfAG5 gene was high in leaves and flowers, but low in pods in transgenic Arabidopsis. The PfAG5 gene was expressed earlier and higher in the resistant (R) than the susceptible (S) P. fugax plants. Furthermore, one protein (FRIGIDA-like) with relevance to flowering time regulation and interacts with PfAG5 in resistant (R) P. fugax was identified by the yeast two-hybrid and pull-down assays. These results suggest that the PfAG5 gene is involved in modulating early flowering in P. fugax.


Asunto(s)
Arabidopsis , Proteínas de Plantas , Arabidopsis/genética , Flores/genética , Resistencia a los Herbicidas/genética , Proteínas de Plantas/genética , Poaceae
18.
Cell Rep ; 36(2): 109373, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34260933

RESUMEN

Drosophila melanogaster Down syndrome cell adhesion molecule (Dscam1) can generate 38,016 different isoforms through largely stochastic, yet highly biased, alternative splicing. These isoforms are required for nervous functions. However, the functional significance of splicing bias remains unknown. Here, we provide evidence that Dscam1 splicing bias is required for mushroom body (MB) axonal wiring. We generate mutant flies with normal overall protein levels and an identical number but global changes in exon 4 and 9 isoform bias (DscamΔ4D-/- and DscamΔ9D-/-), respectively. In contrast to DscamΔ4D-/-, DscamΔ9D-/- exhibits remarkable MB defects, suggesting a variable domain-specific requirement for isoform bias. Importantly, changes in isoform bias cause axonal defects but do not influence the self-avoidance of axonal branches. We conclude that, in contrast to the isoform number that provides the molecular basis for neurite self-avoidance, isoform bias may play a role in MB axonal wiring by influencing non-repulsive signaling.


Asunto(s)
Moléculas de Adhesión Celular/genética , Proteínas de Drosophila/genética , Intrones/genética , Mutagénesis/genética , Neuronas/metabolismo , Empalme del ARN/genética , ARN/metabolismo , Alelos , Animales , Axones/metabolismo , Emparejamiento Base/genética , Secuencia de Bases , Moléculas de Adhesión Celular/química , Moléculas de Adhesión Celular/metabolismo , Dendritas/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Exones/genética , Femenino , Masculino , Cuerpos Pedunculados/metabolismo , Fenotipo , Dominios Proteicos , Isoformas de Proteínas/metabolismo , Eliminación de Secuencia
19.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): o3168, 2010 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-21589464

RESUMEN

The title compound, C(26)H(24)FNO(3), is a critical inter-mediate of a selective and competitive inhibitor of the enzyme 3-hy-droxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase. Inter-molecular N-H⋯O hydrogen bonding generates a chain along [give direction] that is the dominant inter-action in the crystal packing. Inter-molecular C-H⋯O inter-actions are also observed.

20.
Front Plant Sci ; 11: 525, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32457775

RESUMEN

The evolution of herbicide resistance in weedy plants leads to various adaptation traits including flowering time and seed germination. In our previous studies, we found an association of the early flowering phenotype with the ACCase inhibitor herbicide resistance genotype in a population of Polypogon fugax. MADS-box transcription factors are known to play pivotal roles in regulating plant flowering time. In this study, a SHORT VEGETATIVE PHASE (SVP)-like gene, belonging to the StMADS11 subfamily in the MADS-box family, was cloned from the early flowering P. fugax population (referred to as PfMADS16) and resistant to the herbicide clodinafop- propargyl. Overexpression of the SVP-like gene PfMADS16 in Arabidopsis thaliana resulted in early flowering and seed abortion. This is consistent with the phenotypic characters of resistant P. fugax plants, but contrary to the conventional role of SVP-like genes that usually suppress flowering. In addition, down regulation of the seed formation gene AtKTN1 in flowers of PfMADS16 transgenic Arabidopsis plants indicates that PfMADS16 may be indirectly associated with seed viability. Furthermore, one protein (PfMADS2) from the APETALA1 (AP1) subfamily interacting with PfMADS16 in P. fugax was identified with relevance to flowering time regulation. These results suggest that the PfMADS16 gene is an early flowering regulation gene associated with seed formation and viability in resistant P. fugax population. Our study provides potential application of PfMADS16 for integrated weed management (such as genetic-based weed control strategies) aiming to reduce the soil weed seedbank.

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