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1.
Bioorg Med Chem ; 96: 117531, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37972434

RESUMO

The main protease (Mpro) represents one of the most effective and attractive targets for designing anti-SARS-CoV-2 drugs. In this study, we designed and synthesized a novel series of Ebselen derivatives by incorporating privileged fragments from different pockets of the Mpro active site. Among these compounds, 11 compounds showed submicromolar activity in the FRET-based SARS-CoV-2 Mpro inhibition assay, with IC50 values ranging from 233 nM to 550 nM. Notably, compound 3a displayed submicromolar Mpro activity (IC50 = 364 nM) and low micromolar antiviral activity (EC50 = 8.01 µM), comparable to that of Ebselen (IC50 = 339 nM, EC50 = 3.78 µM). Time-dependent inhibition assay confirmed that these compounds acted as covalent inhibitors. Taken together, our optimization campaigns thoroughly explored the structural diversity of Ebselen and verified the impact of specific modifications on potency against Mpro.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Azóis/farmacologia , Relação Estrutura-Atividade , Inibidores de Proteases/farmacologia , Antivirais/farmacologia , Simulação de Acoplamento Molecular
2.
Int J Mol Sci ; 24(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36902361

RESUMO

Filamentation temperature-sensitive H (FtsH) is a proteolytic enzyme that plays an important role in plant photomorphogenesis and stress resistance. However, information regarding the FtsH family genes in pepper is limited. In our research, through genome-wide identification, 18 members of the pepper FtsH family (including five FtsHi members) were identified and renamed based on phylogenetic analysis. CaFtsH1 and CaFtsH8 were found to be essential for pepper chloroplast development and photosynthesis because FtsH5 and FtsH2 were lost in Solanaceae diploids. We found that the CaFtsH1 and CaFtsH8 proteins were located in the chloroplasts and specifically expressed in pepper green tissues. Meanwhile, CaFtsH1 and CaFtsH8-silenced plants created by virus-induced gene silencing exhibited albino leaf phenotypes. In addition, CaFtsH1-silenced plants were observed to contain very few dysplastic chloroplasts and lost the capacity for photoautotrophic growth. Transcriptome analysis revealed that the expression of chloroplast-related genes such as those coding the photosynthesis-antenna protein and structural proteins was downregulated in CaFtsH1-silenced plants, resulting in the inability to form normal chloroplasts. This study improves our understanding of pepper chloroplast formation and photosynthesis through the identification and functional study of CaFtsH genes.


Assuntos
Cloroplastos , Fotossíntese , Filogenia , Cloroplastos/metabolismo , Peptídeo Hidrolases/metabolismo , Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas
3.
Int J Mol Sci ; 24(24)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38139237

RESUMO

Sugars will eventually be exported transporters (SWEETs) are a novel class of sugar transport proteins that play a crucial role in plant growth, development, and response to stress. However, there is a lack of systematic research on SWEETs in Capsicum annuum L. In this study, 33 CaSWEET genes were identified through bioinformatics analysis. The Ka/Ks analysis indicated that SWEET genes are highly conserved not only among peppers but also among Solanaceae species and have experienced strong purifying selection during evolution. The Cis-elements analysis showed that the light-responsive element, abscisic-acid-responsive element, jasmonic-acid-responsive element, and anaerobic-induction-responsive element are widely distributed in the promoter regions of CaSWEETs. The expression pattern analysis revealed that CaSWEETs exhibit tissue specificity and are widely involved in pepper growth, development, and stress responses. The post-transcription regulation analysis revealed that 20 pepper miRNAs target and regulate 16 CaSWEETs through cleavage and translation inhibition mechanisms. The pathogen inoculation assay showed that CaSWEET16 and CaSWEET22 function as susceptibility genes, as the overexpression of these genes promotes the colonization of pathogens, whereas CaSWEET31 functions as a resistance gene. In conclusion, through systematic identification and characteristic analysis, a comprehensive understanding of CaSWEET was obtained, which lays the foundation for further studies on the biological functions of SWEET genes.


Assuntos
Capsicum , Capsicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Genes de Plantas , Família Multigênica , Regulação da Expressão Gênica de Plantas , Filogenia
4.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674730

RESUMO

This study presents proof of concept for designing a novel HIV-1 covalent inhibitor targeting the highly conserved Tyr318 in the HIV-1 non-nucleoside reverse transcriptase inhibitors binding pocket to improve the drug resistance profiles. The target inhibitor ZA-2 with a fluorosulfate warhead in the structure was found to be a potent inhibitor (EC50 = 11-246 nM) against HIV-1 IIIB and a panel of NNRTIs-resistant strains, being far superior to those of NVP and EFV. Moreover, ZA-2 was demonstrated with lower cytotoxicity (CC50 = 125 µM). In the reverse transcriptase inhibitory assay, ZA-2 exhibited an IC50 value of 0.057 µM with the ELISA method, and the MALDI-TOF MS data demonstrated the covalent binding mode of ZA-2 with the enzyme. Additionally, the molecular simulations have also demonstrated that compounds can form covalent binding to the Tyr318.


Assuntos
Fármacos Anti-HIV , HIV-1 , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/química , HIV-1/metabolismo , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/química , Transcriptase Reversa do HIV/metabolismo , Desenho de Fármacos , Relação Estrutura-Atividade
5.
Bioorg Med Chem ; 53: 116531, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34890994

RESUMO

To explore the chemical space around the entrance channel of the HIV-1 reverse transcriptase (RT) binding pocket, we innovatively designed and synthesized a series of novel indolylarylsulfones (IASs) bearing phenylboronic acid and phenylboronate ester functionalities at the indole-2-carboxamide as new HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs) through structure-based drug design. All the newly synthesized compounds exhibited excellent to moderate potency against wild-type (WT) HIV-1 with EC50 values ranging from 6.7 to 42.6 nM. Among all, (3-ethylphenyl)boronic acid substituted indole-2-carboxamide and (4-ethylphenyl) boronate ester substituted indole-2-carboxamide were found to be the most potent inhibitors (EC50 = 8.5 nM, SI = 3310; EC50 = 6.7 nM, SI = 3549, respectively). Notably, (3-ethylphenyl)boronic acid substituted indole-2-carboxamide maintained excellent activities against the single HIV-1 mutants L100I (EC50 = 7.3 nM), K103N (EC50 = 9.2 nM), as well as the double mutant V106A/F227L (EC50 = 21.1 nM). Preliminary SARs and molecular modelling studies are also discussed in detail.


Assuntos
Fármacos Anti-HIV/farmacologia , Ácidos Borônicos/farmacologia , Ésteres/farmacologia , Indóis/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Sulfonas/farmacologia , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Ácidos Borônicos/química , Relação Dose-Resposta a Droga , Ésteres/química , Transcriptase Reversa do HIV/antagonistas & inibidores , Transcriptase Reversa do HIV/metabolismo , HIV-1/efeitos dos fármacos , HIV-1/enzimologia , Indóis/química , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Inibidores da Transcriptase Reversa/síntese química , Inibidores da Transcriptase Reversa/química , Solubilidade , Relação Estrutura-Atividade , Sulfonas/química , Água/química
6.
Molecules ; 28(1)2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36615354

RESUMO

The Coronavirus Disease 2019 (COVID-19) and dengue fever (DF) pandemics both remain to be significant public health concerns in the foreseeable future. Anti-SARS-CoV-2 drugs and vaccines are both indispensable to eliminate the epidemic situation. Here, two piperazine-based polyphenol derivatives DF-47 and DF-51 were identified as potential inhibitors directly blocking the active site of SARS-CoV-2 and DENV RdRp. Data through RdRp inhibition screening of an in-house library and in vitro antiviral study selected DF-47 and DF-51 as effective inhibitors of SARS-CoV-2/DENV polymerase. Moreover, in silico simulation revealed stable binding modes between the DF-47/DF-51 and SARS-CoV-2/DENV RdRp, respectively, including chelating with Mg2+ near polymerase active site. This work discovered the inhibitory effect of two polyphenols on distinct viral RdRp, which are expected to be developed into broad-spectrum, non-nucleoside RdRp inhibitors with new scaffold.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Polifenóis/farmacologia , RNA Polimerase Dependente de RNA/metabolismo , Antivirais/química , Simulação de Acoplamento Molecular
7.
Plant J ; 103(1): 323-337, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32129912

RESUMO

Cuticular waxes play a crucial role not only in plant defense against biotic and abiotic stresses, but also in the quality and storability of fruits, such as the tomato (Solanum lycopersicum). Although the biosynthetic pathways of waxes have been extensively characterized, the regulatory mechanisms underlying wax biosynthesis in tomato remain largely unclear. Here, we show that Woolly (Wo), a multicellular trichome regulator, is involved in modulating wax biosynthesis in tomato. Wo enhances the expression of the wax biosynthetic genes SlCER6, SlKCR1, and SlPAS2, and the wax transporter gene SlLTP, and thereby promotes wax accumulation. Furthermore, Wo directly binds to the L1-box in the promoter of SlCER6, an essential element of the very-long-chain fatty acid elongase complex. Intriguingly, overexpression (OE) or knock-down of SlMYB31, an MYB transcription factor that physically interacts with Wo in vivo and in vitro, produces marked changes in wax composition, and whereas Wo knock-down inhibits wax accumulation in SlMYB31-OE lines, SlMYB31 knock-down inhibits wax accumulation in Wo-OE lines, implying that these two genes function in the same pathway. Lastly, SlCER6 expression is induced by abscisic acid in a manner that is partially dependent on Wo. These results demonstrate that Wo and SlMYB31 cooperatively control tomato cuticular wax biosynthesis by regulating the expression of SlCER6.


Assuntos
Frutas/metabolismo , Epiderme Vegetal/metabolismo , Proteínas de Plantas/fisiologia , Solanum lycopersicum/metabolismo , Fatores de Transcrição/fisiologia , Ceras/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo
8.
Bioorg Med Chem ; 42: 116239, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34090079

RESUMO

To further explore the chemical space surrounding the "hydrophobic channel" of the NNRTI binding pocket (NNIBP), a new series of diarylpyrimidines (DAPYs) were designed and synthesized as potent HIV-1 non-nucleoside RT inhibitors (NNRTIs). The target compounds were evaluated for anti-HIV potency in MT-4 cells. Most of the synthesized DAPYs exhibited moderate to excellent activity against the HIV-1 wild-type (WT) strain with EC50 values ranging from 16 nM to 0.722 µM. Interestingly, few compounds displayed remarkable activity in inhibiting K103N mutant virus with EC50 values ranging from 39 nM to 1.708 µM. Notably, FS2 (EC50(IIIB) = 16 nM, EC50(K103N) = 39 nM, SI = 294) was identified as the most significant compound, which was considerably more potent than nevirapine, lamivudine, and comparable to zidovudine. Additionally, the HIV-1 RT inhibition assay confirmed their binding target. Preliminary structure-activity relationships (SARs) and molecular modeling studies were also performed, providing significant suggestions for further optimization.


Assuntos
Fármacos Anti-HIV/farmacologia , Descoberta de Drogas , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Inibidores da Transcriptase Reversa/farmacologia , Fármacos Anti-HIV/química , Relação Dose-Resposta a Droga , Transcriptase Reversa do HIV/metabolismo , HIV-1/genética , Humanos , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mutação , Inibidores da Transcriptase Reversa/química , Relação Estrutura-Atividade
9.
Bioorg Chem ; 116: 105353, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34536931

RESUMO

Herein, alkenylpiperidine and alkynylpiperidine moieties were introduced into the left wing of DAPYs (diarylpyrimidines) to explore the new site of the NNIBP (non-nucleoside inhibitor binding pocket) protein-solvent interface region via the structure-based drug design strategy. All the synthesized compounds displayed nanomolar to submicromolar activity against WT (wild-type) HIV-1. Among all, compound FT1 (EC50 = 19 nM) was found to be the most active molecule, which is better than NVP (EC50 = 0.10 µM). In addition, most of the compounds displayed micromolar activity against K103N and E138K mutant strains, while FT1 (EC50(K103N) = 50 nM, EC50(E138K) = 0.19 µM) still has the most effective activity. The molecular dynamics simulation studies revealed that the presence of pyridine moiety of FT1 was essential and played a significant role in its binding with RT (reverse transcriptase).


Assuntos
Fármacos Anti-HIV/farmacologia , Desenho de Fármacos , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Piperidinas/farmacologia , Pirimidinas/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Relação Dose-Resposta a Droga , Transcriptase Reversa do HIV/metabolismo , HIV-1/enzimologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Piperidinas/química , Pirimidinas/síntese química , Pirimidinas/química , Inibidores da Transcriptase Reversa/síntese química , Inibidores da Transcriptase Reversa/química , Relação Estrutura-Atividade
10.
J Exp Bot ; 71(9): 2527-2536, 2020 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31943062

RESUMO

Steroidal glycoalkaloids (SGAs) are cholesterol-derived molecules found in the family Solanaceae. SGA content varies among different plant species and varieties. However, the genetic mechanisms regulating SGA content remain unclear. Here, we demonstrate that genetic variation in GLYCOALKALOID METABOLISM 9 (GAME9) is responsible for the variation in SGA content in tomato (Solanum lycopersicum). During a sequential analysis we found a 1 bp substitution in the AP2/ERF binding domain of GAME9. The 1 bp substitution in GAME9 was significantly associated with high SGA content and determined the binding capacity of GAME9 with the promoter of GAME17, a core SGA biosynthesis gene. The high-SGA GAME9 allele is mainly present in S. pimpinellifolium and S. lycopersicum var. cerasiforme populations and encodes a protein that can bind the GAME17 promoter. In contrast, the low-SGA GAME9 allele is mainly present in the big-fruited varieties of S. lycopersicum and encodes a protein that shows weak binding to the GAME17 promoter. Our findings provide new insight into the regulation of SGA biosynthesis and the factors that affect the accumulation of SGA in tomato.


Assuntos
Solanum lycopersicum , Alelos , Frutas , Solanum lycopersicum/genética , Regiões Promotoras Genéticas
11.
J Org Chem ; 85(13): 8656-8664, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32510222

RESUMO

A concise, recyclable, and efficient process is presented for the preparation of (S)-ketamine (esketamine, (S)-1a) via classic resolution combined with the recycling of the undesired isomer. With commercially available ketone 2 as the starting material, this procedure features three steps including (1) an unique hydroxylation-ring expansion rearrangement, (2) mild amination via methanesulfonate, and (3) chiral separation using L-(+)-tartaric acid. The three simple steps are all performed in mild conditions and (S)-1a tartrate is obtained in 99.5% ee without recrystallization. Subsequently, racemization of the unwanted (R)-1a remained in resolution mother liquor was performed in the presence of a Lewis acid in quantitative yield with >99.0% chemical purity. This original and economical process afforded esketamine in 67.4% (28.9% without racemization) overall yield with two times recycling of the mother liquor without column purification. In addition, this procedure can also be applied to the preparation of (S)-norketamine, which is a safer potential antidepressant.

12.
Plant J ; 96(1): 90-102, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29981215

RESUMO

Trichomes originate from the epidermal cells of nearly all terrestrial plants, which are specialized unicellular or multicellular structures. Although the molecular mechanism regulating unicellular trichome formation has been extensively characterized, most of the genes essential for multicellular trichome formation remain unknown. In this study, we identified an associated locus on the long arm of chromosome 10 using a genome-wide association study (GWAS) on type-I trichomes of 180 diverse Solanum lycopersicum (tomato) accessions. Using map-based cloning we then cloned the key gene controlling the initiation of this type of trichome, named Hair (H), which encodes a single C2H2 zinc-finger protein. Transgenic experiments showed that hair-absent phenotype is caused by the deletion of the entire coding region of H. We identified three alleles of H containing several missense mutations and a nucleotide deletion, which result in amino acid substitutions and a reading frame shift, respectively. In addition, knockdown of H or Woolly (Wo) represses the formation of type-I trichomes, suggesting that both regulators may function as a heterodimer. Direct protein-protein interaction between them was further detected through pull-down and yeast two-hybrid assays. In addition, ectopic expression of H in Nicotiana tabacum (tobacco) and expression of its homologs from Capsicum annuum (pepper) and tobacco in tomato can trigger trichome formation. Taken together, these findings suggest that the H gene may be functionally conserved in multicellular trichome formation in Solanaceae species.


Assuntos
Dedos de Zinco CYS2-HIS2/fisiologia , Proteínas de Plantas/fisiologia , Solanum lycopersicum/metabolismo , Tricomas/crescimento & desenvolvimento , Alelos , Capsicum , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Nicotiana , Técnicas do Sistema de Duplo-Híbrido
13.
BMC Plant Biol ; 19(1): 265, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221088

RESUMO

BACKGROUND: Chloroplast biogenesis, a complex process in higher plants, is the key to photoautotrophic growth in plants. White virescent (wv) mutants have been used to unfold the molecular mechanisms underlying the regulation of chloroplast development and chloroplast gene expression in plants. However, most of genes controlling white virescent phenotype still remain unknown. RESULTS: In this study, we identified a temperature- and light intensity-sensitive mutant, named as wv. The content of chlorophyll was dramatically decreased in the immature leaves of wv mutant under the conditions of low temperature and high-light intensity. TEM observation showed that the chloroplasts in the young leaves of wv mutant lacked an organized thylakoid membrane, whereas crescent-shaped chloroplasts with well-developed stromal and stacked grana thylakoids in the mature leaves were developed. Immunoblot analyses suggested that proteins of photosynthetic complexes were decreased substantially in wv mutants. Based on map-based cloning and transgenic analysis, we determined that the wv phenotype was caused by single base mutation in the first intron of WV gene, which encoded a thioredoxin protein with 365 amino acids. qRT-PCR analysis revealed that the expression of WV gene was significantly down-regulated in wv mutant. In addition, knockdown of WV gene through RNAi also resulted in white virescent young leaves, suggesting that the mutation possibly blocks the differentiation of chloroplasts through inhibiting the expression of WV gene. Furthermore, the expression of WV peaked in apical buds and gradually decreased along with the developmental stage, which was consistent with the wv mutant phenotype. Expression analysis of chloroplast-encoded genes by qRT-PCR showed that the wv mutation affected the expression pattern of chloroplast-encoded PEP dependent genes. CONCLUSION: Our results suggested that wv mutant was sensitive to low temperature and light intensity. WV gene was essential for chloroplast differentiation. A single base mutation in the first intron resulted in down-regulation of WV gene expression, which inhibited the expression of chloroplast-encoded genes, thereby blocking chloroplast formation and chlorophyll synthesis.


Assuntos
Cloroplastos/genética , Solanum lycopersicum/genética , Tiorredoxinas/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Temperatura Baixa , Genes de Plantas , Luz , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/efeitos da radiação , Mutação , Fenótipo , Fotossíntese/genética , Alinhamento de Sequência , Tiorredoxinas/fisiologia
14.
Entropy (Basel) ; 21(5)2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33267170

RESUMO

Inspired by the pioneering work of the information bottleneck (IB) principle for Deep Neural Networks' (DNNs) analysis, we thoroughly study the relationship among the model accuracy, I ( X ; T ) and I ( T ; Y ) , where I ( X ; T ) and I ( T ; Y ) are the mutual information of DNN's output T with input X and label Y. Then, we design an information plane-based framework to evaluate the capability of DNNs (including CNNs) for image classification. Instead of each hidden layer's output, our framework focuses on the model output T. We successfully apply our framework to many application scenarios arising in deep learning and image classification problems, such as image classification with unbalanced data distribution, model selection, and transfer learning. The experimental results verify the effectiveness of the information plane-based framework: Our framework may facilitate a quick model selection and determine the number of samples needed for each class in the unbalanced classification problem. Furthermore, the framework explains the efficiency of transfer learning in the deep learning area.

15.
Molecules ; 23(12)2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30501039

RESUMO

Twelve impurities (process-related and degradation) in lisdexamfetamine dimesylate (LDX), a central nervous system (CNS) stimulant drug, were first separated and quantified by high-performance liquid chromatography (HPLC) and then identified by liquid chromatography mass spectrometry (LC-MS). The structures of the twelve impurities were further confirmed and characterized by IR, HRMS and NMR analyses. Based on the characterization data, two previously unknown impurities formed during the process development and forced degradation were proposed to be (2S)-2,6-di-(lysyl)-amino-N-[(1S)-1-methyl-2-phenyl ethyl]hexanamide (Imp-H) and (2S)-2,6-diamino-N-[(1S)-1-methyl-2-(2-hydroxyphenyl)ethyl] hexanamide (Imp-M). Furthermore, these two compounds are new. Probable mechanisms for the formation of the twelve impurities were discussed based on the synthesis route of LDX. Superior separation was achieved on a YMC-Pack ODS-AQ S5 120A silica column (250 × 4.6 mm × 5 µm) using a gradient of a mixture of acetonitrile and 0.1% aqueous methanesulfonic acid solution. The HPLC method was optimized in order to separate, selectively detect, and quantify all the impurities. The full identification and characterization of these impurities should prove useful for quality control in the manufacture of lisdexamfetamine dimesylate.


Assuntos
Contaminação de Medicamentos , Dimesilato de Lisdexanfetamina/análise , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Limite de Detecção , Dimesilato de Lisdexanfetamina/química , Espectroscopia de Prótons por Ressonância Magnética , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
16.
Theor Appl Genet ; 129(8): 1531-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27151537

RESUMO

KEY MESSAGE: Using map-based cloning, we delimited the dialytic gene to an approximately 109-kb fragment, which controls multicellular trichome formation and stamen development in tomato. Trichomes exist in the epidermis of nearly all terrestrial plants, including unicellular and multicellular types. The molecular mechanism of unicellular trichomes in Arabidopsis is well characterized. However, knowledge about the regulatory pathway of multicellular trichomes in tomato (Solanum lycopersicum) is limited. Phenotypic analysis of the dialytic (dl) mutant LA3724 demonstrated that the trichomes are forked and the stamens are unclosed. To clone and characterize dl, we mapped this gene to an approximately 109-kb fragment using two F2 populations derived from the two crosses of dl mutant: LA3724 × IL8-1 and LA3724 × LA1589 (Solanum pimpinellifolium). Two types of molecular markers were utilized in this study, including cleaved amplified polymorphic sequences and insertion-deletion events. Sequence analysis predicted the presence of seven putative open reading frames, including two unknown proteins, two phospholipase Ds, glycosyl hydrolase family 5 protein/cellulose, choline/ethanolamine kinase, and aquaporin-like protein. The aquaporin-like protein gene was evidently upregulated in dl mutant. Thus, we inferred that this gene is a potential candidate for the phenotypes. The results provide a basis to elucidate the regulatory pathway responsible for trichome formation and stamen development in tomato.


Assuntos
Mapeamento Cromossômico , Flores/crescimento & desenvolvimento , Solanum lycopersicum/genética , Tricomas/crescimento & desenvolvimento , Clonagem Molecular , Cruzamentos Genéticos , DNA de Plantas/genética , Flores/genética , Ligação Genética , Mutação INDEL , Solanum lycopersicum/crescimento & desenvolvimento , Fases de Leitura Aberta , Fenótipo , Tricomas/genética
17.
BMC Genomics ; 16: 868, 2015 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-26503424

RESUMO

BACKGROUND: Trichomes, developing from the epidermis of nearly all terrestrial plants, provide good structural resistance against insect herbivores and an excellent model for studying the molecular mechanisms underlying cell fate determination. Regulation of trichomes in Rosids has been well characterized. However, little is known about the cell proliferation molecular processes during multicellular trichome formation in Asterids. RESULTS: In this study, we identified two point mutations in a novel allele (Wov) at Wo locus. Ectopic expression of Wov in tobacco and potato induces much more trichome formation than wild type. To gain new insights into the underlying mechanisms during the processes of these trichomes formation, we compared the gene expression profiles between Wov transgenic and wild-type tobacco by RNA-seq analysis. A total of 544 co-DEGs were detected between transgenic and wild-type tobacco. Functional assignments of the co-DEGs indicated that 33 reliable pathways are altered in transgenic tobacco plants. The most noticeable pathways are fatty acid metabolism, amino acid biosynthesis and metabolism, and plant hormone signal transduction. Results suggest that these enhanced processes are critical for the cell proliferation during multicellular trichome formation in transgenic plants. In addition, the transcriptional levels of homologues of trichome regulators in Rosids were not significantly changed, whereas homologues of genes (Wo and SlCycB2) in Asterids were significantly upregulated in Wov transgenic tobacco plants. CONCLUSIONS: This study presents a global picture of the gene expression changes induced by Wov-gene in tobacco. And the results provided us new insight into the molecular processes controlling multicellular formation in tobacco. Furthermore, we inferred that trichomes in solanaceous species might share a common network.


Assuntos
Nicotiana/citologia , Nicotiana/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Solanum lycopersicum/genética , Tricomas/citologia , Tricomas/metabolismo , Proliferação de Células/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Nicotiana/genética , Transcriptoma/genética , Tricomas/genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-38885109

RESUMO

In recent years, the neural implicit surface has emerged as a powerful representation for multi-view surface reconstruction due to its simplicity and state-of-the-art performance. However, reconstructing smooth and detailed surfaces in indoor scenes from multi-view images presents unique challenges. Indoor scenes typically contain large texture-less regions, making the photometric loss unreliable for optimizing the implicit surface. Previous work utilizes monocular geometry priors to improve the reconstruction in indoor scenes. However, monocular priors often contain substantial errors in thin structure regions due to domain gaps and the inherent inconsistencies when derived independently from different views. This paper presents DebSDF to address these challenges, focusing on the utilization of uncertainty in monocular priors and the bias in SDF-based volume rendering. We propose an uncertainty modeling technique that associates larger uncertainties with larger errors in the monocular priors. High-uncertainty priors are then excluded from optimization to prevent bias. This uncertainty measure also informs an importance-guided ray sampling and adaptive smoothness regularization, enhancing the learning of fine structures. We further introduce a bias-aware signed distance function to density transformation that takes into account the curvature and the angle between the view direction and the SDF normals to reconstruct fine details better. Our approach has been validated through extensive experiments on several challenging datasets, demonstrating improved qualitative and quantitative results in reconstructing thin structures in indoor scenes, thereby outperforming previous work.

19.
IEEE J Biomed Health Inform ; 28(4): 2211-2222, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38289848

RESUMO

Three-dimensional (3D) ultrasound imaging technique has been applied for scoliosis assessment, but the current assessment method only uses coronal projection images and cannot illustrate the 3D deformity and vertebra rotation. The vertebra detection is essential to reveal 3D spine information, but the detection task is challenging due to complex data and limited annotations. We propose VertMatch to detect vertebral structures in 3D ultrasound volume containing a detector and classifier. The detector network finds the potential positions of structures on transverse slice globally, and then the local patches are cropped based on detected positions. The classifier is used to distinguish whether the patches contain real vertebral structures and screen the predicted positions from the detector. VertMatch utilizes unlabeled data in a semi-supervised manner, and we develop two novel techniques for semi-supervised learning: 1) anatomical prior is used to acquire high-quality pseudo labels; 2) inter-slice consistency is used to utilize more unlabeled data by inputting multiple adjacent slices. Experimental results demonstrate that VertMatch can detect vertebra accurately in ultrasound volume and outperforms state-of-the-art methods. Moreover, VertMatch is also validated in automatic spinous process angle measurement on forty subjects with scoliosis, and the results illustrate that it can be a promising approach for the 3D assessment of scoliosis.


Assuntos
Escoliose , Humanos , Escoliose/diagnóstico por imagem , Imageamento Tridimensional/métodos , Coluna Vertebral/diagnóstico por imagem , Ultrassonografia
20.
J Med Chem ; 67(6): 5032-5052, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38482820

RESUMO

Gout and hyperuricemia are metabolic diseases characterized with high serum uric acid (SUA) levels that significantly impact human health. Lesinurad, a uricosuric agent, is limited to concurrent use with xanthine oxidase inhibitors (XOIs) in clinical practice due to its restricted efficacy and potential nephrotoxicity. Herein, extensive structural modifications of lesinurad were conducted through scaffold hopping and substituent modification strategies, affording 54 novel derivatives containing pyrimidine-fused cyclic structures. Notably, the thienopyrimidine compound 29 demonstrated a remarkable 2-fold increase in SUA-lowering in vivo activity compared to lesinurad, while exhibiting potent inhibitory activity against the urate transporter 1 (URAT1, IC50 = 2.01 µM) and glucose transporter 9 (GLUT9, IC50 = 18.21 µM). Furthermore, it possessed a lower effective dosage of 0.5 mg/kg, favorable safety profile without any apparent acute toxicity at doses of 1000 mg/kg, and improved pharmacokinetic properties. Overall, we have discovered an efficacious URAT1/GLUT9 dual inhibitor for inhibiting urate reabsorption with favorable pharmacokinetic profiles.


Assuntos
Gota , Hiperuricemia , Transportadores de Ânions Orgânicos , Tioglicolatos , Triazóis , Humanos , Ácido Úrico/uso terapêutico , Gota/tratamento farmacológico , Hiperuricemia/tratamento farmacológico , Uricosúricos/uso terapêutico , Pirimidinas/toxicidade , Pirimidinas/uso terapêutico , Proteínas Facilitadoras de Transporte de Glucose , Proteínas de Transporte de Cátions Orgânicos
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