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1.
Trends Genet ; 38(11): 1147-1169, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35853769

RESUMO

Genome editing continues to revolutionize biological research. Due to its simplicity and flexibility, CRISPR/Cas-based editing has become the preferred technology in most systems. Cas nucleases tolerate fusion to large protein domains, thus allowing combination of their DNA recognition properties with new enzymatic activities. Fusion to nucleoside deaminase or reverse transcriptase domains has produced base editors and prime editors that, instead of generating double-strand breaks in the target sequence, induce site-specific alterations of single (or a few adjacent) nucleotides. The availability of protein-only genome editing reagents based on transcription activator-like effectors has enabled the extension of base editing to the genomes of chloroplasts and mitochondria. In this review, we summarize currently available base editing methods for nuclear and organellar genomes. We highlight recent advances with improving precision, specificity, and efficiency and discuss current limitations and future challenges. We also provide a brief overview of applications in agricultural biotechnology and gene therapy.


Assuntos
Sistemas CRISPR-Cas , Nucleosídeo Desaminases , Sistemas CRISPR-Cas/genética , DNA/genética , Quebras de DNA de Cadeia Dupla , Edição de Genes/métodos , Nucleosídeo Desaminases/genética , Nucleosídeo Desaminases/metabolismo , Nucleotídeos , DNA Polimerase Dirigida por RNA/genética , DNA Polimerase Dirigida por RNA/metabolismo , Efetores Semelhantes a Ativadores de Transcrição/genética , Efetores Semelhantes a Ativadores de Transcrição/metabolismo
2.
Opt Express ; 32(4): 6232-6240, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439331

RESUMO

We propose what we believe is a novel format conversion scheme using a few-mode fiber Bragg grating (FM-FBG) that can perform multichannel format conversion from carrier-suppressed return-to-zero (CSRZ) to non-return-to-zero (NRZ) for both LP01 and LP11. The multichannel spectral response of FM-FBG is designed according to the algebraic difference between the CSRZ and NRZ spectra outlines. Additionally, the FM-FBG response spectra of LP11 are designed to shift with that of LP01 by the WDM-MDM channel spacing for filtering both modes together. Numerical results demonstrate the successful conversion of both LP01 and LP11 channels, carrying four channels of 200-GHz-spaced CSRZ signals at 40 Gbit/s, into NRZ signals with a high Q-factor (exceeding 14 dB), and the converted NRZ signals exhibit clean and open eye diagrams. Furthermore, the performance analysis also shown that our proposed FM-FBG is robust to central wavelength detuning.

3.
J Asian Nat Prod Res ; : 1-7, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920362

RESUMO

Twelve compounds, comprising of four new ones, 6ß,7α-limondiol (1) and ethyl 19-hydroxyisoobacunoate diosphenol (2), N-benzoyl 3-prenyltyramine (9) and 9-O-methyl integrifoliodiol (12), were isolated from the twigs with leaves of Tetradium trichotomum. The structures were elucidated by analysis of MS, NMR, and single-crystal X-ray diffraction. Compounds 1, 6, 8, 9 and 12 exhibited immunosuppressive activities in vitro against the proliferation of ConA-induced T lymphocytes and LPS-induced B cells.

4.
World J Microbiol Biotechnol ; 40(2): 78, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38253730

RESUMO

Efforts to curtail the escalating health threat posed by methicillin-resistant Staphylococcus aureus (MRSA), a formidable superbug, necessitate the development of innovative treatment strategies. Leveraging potential compounds from natural sources in tandem with antibiotics has emerged as a promising approach against MRSA. These strategies should enhance the antibiotic efficacy, reduce dosage and toxicity, and bypass MRSA resistance. In this study, we used a checkerboard assay to illustrate the significant synergistic anti-MRSA effect of shikimic acid (SA), a naturally occurring compound, and ceftiofur (CF). Time-kill curves further revealed that a combination of 1/4 of the minimum inhibitory concentration (MIC) of SA and 1/8 MIC of the sodium CF eradicated MRSA within 2 h, with no noticeable toxicity observed with these concentrations. In vivo experiments confirmed that this combination therapy demonstrated robust antimicrobial activity against MRSA-induced bacteremia in mice, significantly reducing bacterial loads in the kidneys, liver, and spleen, attenuating inflammatory cell infiltration, and alleviating pathological damage. This study not only offers a compelling strategy, capitalizing on the synergistic potential of SA and CF, to rapidly address antibiotic resistance but also contributes significantly to the refinement of antimicrobial therapeutic strategies.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Animais , Camundongos , Ácido Chiquímico/farmacologia , Cefalosporinas/farmacologia , Antibacterianos/farmacologia
5.
Opt Express ; 31(11): 17528-17536, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381483

RESUMO

We propose a novel format conversion scheme, which can implement multichannel format conversion from return-to-zero (RZ) to non-return-to-zero (NRZ) for both LP01 and LP11 simultaneously by designing a few-mode fiber Bragg grating (FM-FBG) with comb spectra. To achieve filtering for all channels of the two modes, the FM-FBG response spectra of LP11 is designed to shift with that of LP01 by the WDM-MDM channel spacing. This approach is realized by carefully selecting the specifications of the few-mode fiber (FMF) to fulfill the requirements of the effective refractive index difference between LP01 and LP11. Each single-channel outline of the FM-FBG response spectra is designed according to the algebraic difference between the RZ and NRZ spectra. Numerical results show that both LP01 and LP11 channels with 300-GHz-spaced RZ signals at 40 Gbit/s can be converted into NRZ signals simultaneously, and the converted NRZ signals have high Q-factor and their eye diagrams are clean and open.

6.
Biosci Biotechnol Biochem ; 87(8): 819-824, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37279892

RESUMO

Arctigenin (ARG) has potent antifatigue activity, but its clinical application has been restricted for its poor water solubility. In this study, seven ARG derivatives containing different amino acids coupled via an ethoxy linker were synthesized, and tested for their solubility, as well as activities to improve exercise performance in mice. All of the derivatives showed improved solubility compared to that of ARG. Derivative Z-A-6 exhibited the highest activity, showing that the mice ran a 4.88-fold greater distance in the running wheel test and swam a 2.86-fold greater time in the swimming test than those in the blank control group. Z-A-6 treatment increased the plasma superoxide dismutase and catalase concentrations as well as reduced lactic acid and blood urea nitrogen accumulation during exercise. Z-A-6 treatment enhanced the phosphorylation of adenosine monophosphate-activated protein kinase, and no acute toxicity was observed. The results will contribute to the development of potential antifatigue agents.


Assuntos
Furanos , Lignanas , Camundongos , Animais , Furanos/farmacologia , Furanos/química , Lignanas/farmacologia , Lignanas/química , Superóxido Dismutase/metabolismo , Natação
7.
Med Sci Monit ; 29: e938912, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36922715

RESUMO

BACKGROUND This study aimed to evaluate the safety and efficacy of portal vein puncture with a new guidance system using double C-arm digital subtraction angiography (DSA) during transjugular intrahepatic portosystemic shunt (TIPS) placement. MATERIAL AND METHODS The procedure details of TIPS placements performed on 39 patients in our center between January and December 2021 were retrospectively analyzed. The procedure was performed under double C-arm DSA guidance (study group) and C-arm DSA (control group) in 18 and 21 patients, respectively. We analyzed the procedure's technical success, duration of the overall procedure, portal vein puncture, fluoroscopy, radiation exposure, complications, and mortality and morbidity rates 30 days after the procedure. RESULTS TIPS placement was performed successfully in all patients. The mean portal vein puncture time in the study group (9±5.7 min) was significantly shorter than in the control group (33±14.9 min, p=0.02). The complete mean dose area product of the procedure showed no significant differences (study group, 126±53 Gy/cm²; control group. 142±66 Gy/cm²; p=0.42). The intraprocedural complication rates were 0% and 19% in the study and control groups, respectively (p=0.04). The 30-day post-procedural mortality rate in the control group was 4.8% (1/21), with no deaths from technical complications. CONCLUSIONS Double C-arm DSA guidance is a safe and effective method to assist TIPS placement. This approach may result in shorter portal vein puncture time and lower intraprocedural complication rates.


Assuntos
Derivação Portossistêmica Transjugular Intra-Hepática , Humanos , Derivação Portossistêmica Transjugular Intra-Hepática/métodos , Angiografia Digital , Estudos Retrospectivos , Veia Porta/cirurgia , Punções , Resultado do Tratamento
8.
Ann Vasc Surg ; 96: 374-381, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37230316

RESUMO

BACKGROUND: In the last decade, the microwave ablation catheter specifically for treating lower extremity varicose veins has become popular. However, imited data is available on the efficacy, analysis, and evaluation of endovenous microwave ablation (EMWA) in treating SSV insufficiency. Our objective is to evaluated the feasibility, safety, and 1-year outcomes of EMWA and concomitant foam sclerotherapy of primary small saphenous vein (SSV) insufficiency. METHODS: Our team carried out a single-center, retrospective analysis of 24 patients treated with EMWAand concomitant foam sclerotherapy for primary SSV insufficiency. All operations were performed using a MWA catheter and polidocanol for the trunk and branches of the SSV, respectively. The SSV occlusion rate was assessed at the 6- and 12-month follow-up examinations using duplex ultrasound. Secondary outcomes included the Clinical, Etiological, Anatomical, Pathophysiological (CEAP) clinical class; Venous Clinical Severity Score (VCSS); Aberdeen Varicose Vein Questionnaire (AVVQ); periprocedural pain; and complications. RESULTS: 100% of the cases have been technically successful. At the 6-month follow-up, all treated SSVs were occluded. The 12-month assessment duplex doppler showed anatomical success in patients with 95.8% (95% confidence interval, 0.756-0.994). The CEAP clinical class, VCSS, and the AVVQ had decreased significantly at the 6- and 12-month follow-up, respectively. CONCLUSIONS: EMWA and concomitant foam sclerotherapy is a feasible and effective technique for treating SSV insufficiency.


Assuntos
Terapia a Laser , Varizes , Insuficiência Venosa , Humanos , Escleroterapia/efeitos adversos , Escleroterapia/métodos , Seguimentos , Veia Safena/cirurgia , Estudos Retrospectivos , Micro-Ondas/efeitos adversos , Insuficiência Venosa/diagnóstico por imagem , Insuficiência Venosa/terapia , Terapia a Laser/efeitos adversos , Resultado do Tratamento , Ultrassonografia de Intervenção , Varizes/diagnóstico por imagem , Varizes/terapia , Varizes/complicações
9.
Pestic Biochem Physiol ; 192: 105393, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37105631

RESUMO

Rhopalosiphum padi (L.) is an important cosmopolitan pest of cereal crops. Thiamethoxam is widely used for control R. padi in some regions. Chemosensory proteins (CSPs) are a class of transporter proteins in arthropods which play a key role in various physiological processes including response to insecticide exposure. However, the role of R. padi CSPs (RpCSPs) in insecticide binding and susceptibility has not been well clarified. In this study, we found that the expression levels of RpCSP1, RpCSP4, RpCSP5, RpCSP7, RpCSP10 were dramatically upregulated after exposure to thiamethoxam. Suppression of RpCSP4 and RpCSP5 transcription by RNA interference significantly enhanced the susceptibility of R. padi to thiamethoxam. Molecular docking and fluorescence competitive binding showed that RpCSP4 and RpCSP5 had high binding affinity with thiamethoxam. The present results prove that RpCSP4 and RpCSP5 are related to insecticide resistance through high binding affinity to reduce the toxicity of insecticide.


Assuntos
Afídeos , Inseticidas , Animais , Tiametoxam/metabolismo , Inseticidas/toxicidade , Inseticidas/metabolismo , Afídeos/genética , Afídeos/metabolismo , Avena , Simulação de Acoplamento Molecular
10.
Vasa ; 52(6): 355-365, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37779391

RESUMO

Insufficiency of the small saphenous vein causes 15% of varicose veins in the lower extremities. Endovenous ablation for the treatment of small saphenous vein varices has become a trend, and an increasing number of studies have reported the effects of different types of endovenous ablation in patients with small saphenous varicose veins. The purpose of this systematic review is to summarize the results of existing studies on endovenous ablation for the treatment of small saphenous varicose veins, compare its role and efficacy, and provide insights into the future development of endovenous ablation for treating small saphenous varicose veins. A systematic review of literature published from January 1, 2002 to January 1, 2022 was conducted from PubMed, Embase, and China Academic Journals full-text databases. The pre-determined inclusion criteria were clinical literature of endovenous ablation for treating small saphenous varicose veins. Keywords included "ablation", "small saphenous vein", "lesser saphenous vein", "short saphenous vein", "xiaoyinjingmai" and "xiaorong". Of the 506 articles screened, 33 articles were included in this review: 19 articles were related to endovenous laser ablation, five were related to mechanochemical ablation, seven were related to radiofrequency ablation, and two were related to both endovenous laser ablation and radiofrequency ablation. The anatomical success rate of endovenous laser ablation, radiofrequency ablation, and mechanochemical ablation were 94.3%, 96.0%, and 88.1%, respectively, and the heterogeneities were all moderate. Most of the current studies are of a low-quality level of research. Hence, long-term follow-up studies and large-scale randomized controlled trials are required to obtain high-quality evidence. Although the gold standard for the treatment of small saphenous vein insufficiency remains unclear, endovenous ablation is still the recommended method.


Assuntos
Terapia a Laser , Varizes , Insuficiência Venosa , Humanos , Veia Safena/diagnóstico por imagem , Veia Safena/cirurgia , Varizes/diagnóstico por imagem , Varizes/cirurgia , Escleroterapia/efeitos adversos , Escleroterapia/métodos , Terapia a Laser/efeitos adversos , Terapia a Laser/métodos , China , Resultado do Tratamento , Insuficiência Venosa/diagnóstico por imagem , Insuficiência Venosa/cirurgia
11.
Plant Biotechnol J ; 20(5): 876-885, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34890109

RESUMO

Rice blast and bacterial blight represent two of major diseases having devastating impact on the yield of rice in most rice-growing countries. Developments of resistant cultivars are the most economic and effective strategy to control these diseases. Here, we used CRISPR/Cas9-mediated gene editing to rapidly install mutations in three known broad-spectrum blast-resistant genes, Bsr-d1, Pi21 and ERF922, in an indica thermosensitive genic male sterile (TGMS) rice line Longke638S (LK638S). We obtained transgene-free homozygous single or triple mutants in T1 generations. While all single and triple mutants showed increased resistance to rice blast compared with wild type, the erf922 mutants displayed the strongest blast resistance similar with triple mutants. Surprisingly, we found that Pi21 or ERF922 single mutants conferred enhanced resistance to most of tested bacterial blight. Both resistances in mutants were attribute to the up-regulation of SA- and JA-pathway associated genes. Moreover, phenotypic analysis of these single mutants in paddy fields revealed that there were no trade-offs between resistances and main agricultural traits. Together, our study provides a rapid and effective way to generate rice varieties with resistance to both rice blast and bacterial blight.


Assuntos
Resistência à Doença , Oryza , Sistemas CRISPR-Cas/genética , Resistência à Doença/genética , Edição de Genes , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
12.
Plant Cell ; 30(4): 889-906, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29610210

RESUMO

Panicle size is a critical determinant of grain yield in rice (Oryza sativa) and other grain crops. During rice growth and development, spikelet abortion often occurs at either the top or the basal part of the panicle under unfavorable conditions, causing a reduction in fertile spikelet number and thus grain yield. In this study, we report the isolation and functional characterization of a panicle abortion mutant named panicle apical abortion1-1 (paab1-1). paab1-1 exhibits degeneration of spikelets on the apical portion of panicles during late stage of panicle development. Cellular and physiological analyses revealed that the apical spikelets in the paab1-1 mutant undergo programmed cell death, accompanied by nuclear DNA fragmentation and accumulation of higher levels of H2O2 and malondialdehyde. Molecular cloning revealed that paab1-1 harbors a mutation in OsALMT7, which encodes a putative aluminum-activated malate transporter (OsALMT7) localized to the plasma membrane, and is preferentially expressed in the vascular tissues of developing panicles. Consistent with a function for OsALMT7 as a malate transporter, the panicle of the paab1-1 mutant contained less malate than the wild type, particularly at the apical portions, and injection of malate into the paab1-1 panicle could alleviate the spikelet degeneration phenotype. Together, these results suggest that OsALMT7-mediated transport of malate into the apical portion of panicle is required for normal panicle development, thus highlighting a key role of malate in maintaining the sink size and grain yield in rice and probably other grain crops.


Assuntos
Peróxido de Hidrogênio/metabolismo , Malatos/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Oryza/genética , Transporte Biológico , Clonagem Molecular , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Malondialdeído/metabolismo , Transportadores de Ânions Orgânicos/genética , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(9): 951-958, 2021.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-34535212

RESUMO

OBJECTIVES: To study the effect of puromycin aminonucleoside (PAN) on the apoptosis of mouse podocyte clone 5 (MPC-5) and the expression of recombinant human Parkinson's disease 7 (Park7) and to study the protective mechanism of tacrolimus (FK506) against MPC-5 injury. METHODS: MPC-5 cells were cultured in vitro and then divided into three groups: blank control (control), PAN, and FK506. The cells in the PAN group were added with PAN (with a concentration of 50 mg/L) to establish a model of MPC-5 injury, and those in the FK506 group were added with PAN (with a concentration of 50 mg/L) and FK506 (with a concentration of 5 mg/L). An inverted microscope was used to observe the morphology and structure of MPC-5 cells at 12, 24, and 48 hours after treatment. Flow cytometry was used to measure cell apoptosis rate. Quantitative real-time PCR was used to measure the mRNA expression of Park7. Western blot and immunofluorescent staining were used to measure the protein expression of Park7. RESULTS: The control group had a large number of foot processes of the cell body at all time points, with tight connections between cells and a normal morphology. Compared with the control group, the PAN group had a significantly smaller cell volume at all time points, with loose connections between cells and the presence of ruptured cells. Compared with the PAN group, the FK506 group had an increased cell volume at all time points, with tighter connections between cells and a better morphology. The PAN group had a significantly higher apoptosis rate than the control group at all time points. Compared with the PAN group, the FK506 group had a significant reduction in the apoptosis rate at all time points (P<0.01). The PAN group had a significantly higher mRNA expression level of Park7 than the control group at all time points. Compared with the PAN group, the FK506 group had a significant reduction in the mRNA expression level of Park7 at all time points (P<0.01). Western blot showed that the PAN group had a significantly higher protein expression level of Park7 than the control group at all time points. Compared with the PAN group, the FK506 group had a significant reduction in the protein expression level of Park7 at all time points (P<0.01). Immunofluorescent staining showed that in the PAN group, there was a significantly lower expression of Park7 protein in cell membrane and cytoplasm, with a dense cluster distribution and increased fluorescence intensity. Compared with the PAN group, the FK506 group had a significant improvement in the distribution of Park7 protein. CONCLUSIONS: PAN can act on MPC-5 cells and cause morphological and structural damage and apoptosis of MPC-5 cells, as well as upregulated mRNA and protein expression of Park7. FK506 can downregulate the mRNA and protein expression of Park7 in the model of MPC-5 injury, maintain cellular homeostasis, reduce proteinuria, and delay glomerulosclerosis.


Assuntos
Doença de Parkinson , Podócitos , Animais , Camundongos , Proteína Desglicase DJ-1 , Puromicina Aminonucleosídeo/toxicidade , Tacrolimo/farmacologia
14.
BMC Genomics ; 21(1): 427, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32580761

RESUMO

BACKGROUND: Vespa velutina, one of the most aggressive and fearful wasps in China, can cause grievous allergies and toxic reactions, leading to organ failure and even death. However, there is little evidence on molecular data regarding wasps. Therefore, we aimed to provide an insight into the transcripts expressed in the venom gland of wasps. RESULTS: In our study, high-throughput RNA sequencing was performed using the venom glands of four wasp species. First, the mitochondrial cytochrome C oxidase submit I (COI) barcoding and the neighbor joining (NJ) tree were used to validate the unique identity and lineage of each individual species. After sequencing, a total of 127,630 contigs were generated and 98,716 coding domain sequences (CDS) were predicted from the four species. The Gene ontology (GO) enrichment analysis of unigenes revealed their functional role in important biological processes (BP), molecular functions (MF) and cellular components (CC). In addition, c-type, p1 type, p2 type and p3 type were the most commonly found simple sequence repeat (SSR) types in the four species of wasp transcriptome. There were differences in the distribution of SSRs and single nucleotide polymorphisms (SNPs) among the four wasp species. CONCLUSIONS: The transcriptome data generated in this study will improve our understanding on bioactive proteins and venom-related genes in wasp venom gland and provide a basis for pests control and other applications. To our knowledge, this is the first study on the identification of large-scale genomic data and the discovery of microsatellite markers from V. tropica ducalis and V. analis fabricius.


Assuntos
Perfilação da Expressão Gênica/veterinária , Marcadores Genéticos , Proteínas de Insetos/genética , Venenos de Vespas/genética , Vespas/classificação , Animais , Evolução Molecular , Ontologia Genética , Sequenciamento de Nucleotídeos em Larga Escala , Repetições de Microssatélites , Anotação de Sequência Molecular , Filogenia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de RNA , Vespas/genética
15.
J Recept Signal Transduct Res ; 40(3): 273-280, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32102592

RESUMO

Objective: The aim of our study is to investigate the relationship between podocyte autophagy and apoptosis induced by Puromycin Aminonucleoside (PAN) and to clarify its mechanism.Methods: Podocytes were cultured in vitro. The apoptosis rates of each group were detected using flow cytometry. The expression of LC3-II protein and changes in distribution were detected through laser scanning confocal microscope, and the western blot protocol was employed for detection of protein expression of LC3-II. The autophagosomes were detected by transmission electron microscopy.Results: In this study, We found that autophagosome increased followed by apoptosis after podocyte injury. Furthermore, we conformed that the activation of autophagy could inhibit the apoptosis to alleviate the injury of podocyte at an early stage.Conclusions: Autophagy occurred earlier before apoptosis and autophagy mediated podocyte apoptosis induced by PAN. These findings indicate that autophagy may become a novel therapeutic target for the treatment of podocyte injury and proteinuria in the future.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Podócitos/patologia , Puromicina Aminonucleosídeo/farmacologia , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Autofagossomos/ultraestrutura , Western Blotting , Forma Celular/efeitos dos fármacos , Células Cultivadas , Camundongos , Podócitos/efeitos dos fármacos , Podócitos/ultraestrutura , Fatores de Tempo
16.
Nature ; 504(7480): 406-10, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24336215

RESUMO

Strigolactones (SLs), a newly discovered class of carotenoid-derived phytohormones, are essential for developmental processes that shape plant architecture and interactions with parasitic weeds and symbiotic arbuscular mycorrhizal fungi. Despite the rapid progress in elucidating the SL biosynthetic pathway, the perception and signalling mechanisms of SL remain poorly understood. Here we show that DWARF 53 (D53) acts as a repressor of SL signalling and that SLs induce its degradation. We find that the rice (Oryza sativa) d53 mutant, which produces an exaggerated number of tillers compared to wild-type plants, is caused by a gain-of-function mutation and is insensitive to exogenous SL treatment. The D53 gene product shares predicted features with the class I Clp ATPase proteins and can form a complex with the α/ß hydrolase protein DWARF 14 (D14) and the F-box protein DWARF 3 (D3), two previously identified signalling components potentially responsible for SL perception. We demonstrate that, in a D14- and D3-dependent manner, SLs induce D53 degradation by the proteasome and abrogate its activity in promoting axillary bud outgrowth. Our combined genetic and biochemical data reveal that D53 acts as a repressor of the SL signalling pathway, whose hormone-induced degradation represents a key molecular link between SL perception and responses.


Assuntos
Lactonas/metabolismo , Oryza/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Proteólise , Proteínas Ligases SKP Culina F-Box/metabolismo , Transdução de Sinais , Sequência de Aminoácidos , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Mutação/genética , Oryza/genética , Fenótipo , Proteínas de Plantas/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica
18.
Plant Mol Biol ; 92(1-2): 209-22, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27405463

RESUMO

Flowering time determines the adaptability of crop plants to different local environments, thus being one of the most important agronomic traits targeted in breeding programs. Photoperiod is one of the key factors that control flowering in plant. A number of genes that participate in the photoperiod pathway have been characterized in long-day plants such as Arabidopsis, as well as in short-day plants such as Oryza sativa. Of those, CONSTANS (CO) as a floral integrator promotes flowering in Arabidopsis under long day conditions. In rice, Heading date1 (Hd1), a homologue of CO, functions in an opposite way, which inhibits flowering under long day conditions and induces flowering under short day conditions. Here, we show that another CONSTANS-like (COL) gene, OsCOL13, negatively regulates flowering in rice under both long and short day conditions. Overexpression of OsCOL13 delays flowering regardless of day length. We also demonstrated that OsCOL13 has a constitutive and rhythmic expression pattern, and that OsCOL13 is localized to the nucleus. OsCOL13 displays transcriptional activation activity in the yeast assays and likely forms homodimers in vivo. OsCOL13 suppresses the florigen genes Hd3a and RFT1 by repressing Ehd1, but has no relationship with other known Ehd1 regulators as determined by using mutants or near isogenic lines. In addition, the transcriptional level of OsCOL13 significantly decreased in the osphyb mutant, but remained unchanged in the osphya and osphyc mutants. Thus, we conclude that OsCOL13 functions as a negative regulator downstream of OsphyB and upstream of Ehd1 in the photoperiodic flowering in rice.


Assuntos
Oryza/metabolismo , Proteínas de Plantas/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Mutação , Oryza/genética , Proteínas de Plantas/genética
19.
Plant Cell Physiol ; 57(4): 798-812, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26872834

RESUMO

Flowering time, or heading date, is a critical agronomic trait that determines the cropping season and regional adaptability, and ultimately grain yield in rice. A number of genes involved in photoperiodic flowering have been cloned and their roles in modulating expression of the flowering genes have been characterized to a certain extent. However, much less is known about the pathway in transmitting the day length response signal(s) to induce transition to reproductive growth. Here, we report a constitutive flowering repressor OsCOL10, which encodes a member of the CONSTANS-like (COL) family. Transgenic rice plants overexpressing OsCOL10 (driven by a strong promoter or by fusing it to the activation domain of VP64) showed delayed flowering time under both short and long days.OsCOL10 is affected by the circadian clock and is preferentially expressed in leaf mesophyll cells; it is localized to the nucleus and has transcriptional activation activity. Further studies show that OsCOL10 represses the expression of theFT-like genes RFT1 and Hd3a through Ehd1. Transcripts of OsCOL10 are more abundant in plants carrying a functional Ghd7 allele or overexpressing Ghd7 than in Ghd7-deficient plants, thus placing OsCOL10 downstream of Ghd7.Taking these findings together, we conclude that OsCOL10 functions as a flowering time repressor that links Ghd7 and Ehd1 in rice.


Assuntos
Flores/genética , Regulação da Expressão Gênica de Plantas , Oryza/fisiologia , Proteínas de Plantas/genética , Núcleo Celular/metabolismo , Relógios Circadianos/genética , Células do Mesofilo/fisiologia , Oryza/genética , Fotoperíodo , Folhas de Planta/citologia , Folhas de Planta/fisiologia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas
20.
BMC Neurol ; 16(1): 141, 2016 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-27534852

RESUMO

BACKGROUND: Spinal muscular atrophy (SMA) is the most common autosomal recessive disease in children, and the diagnosis is complicated and difficult, especially at early stage. Early diagnosis of SMA is able to improve the outcome of SMA patients. In our study, Real-time PCR was developed to measure the gene mutation or deletion of key genes for SMA and to further analyse genotype-phenotype correlation. METHODS: The multiple real-time PCR for detecting the mutations of survival of motor neuron (SMN), apoptosis inhibitory protein (NAIP) and general transcription factor IIH, polypeptide 2 gene (GTF2H2) was established and confirmed by DNA sequencing and multiplex ligation-dependent probe amplification (MLPA). The diagnosis and prognosis of 141 hospitalized children, 100 normal children and further 2000 cases of dry blood spot (DBS) samples were analysed by this multiple real-time PCR. RESULTS: The multiple real-time PCR was established and the accuracy of it to detect the mutations of SMN, NAIP and GTF2H2 was at least 98.8 % comparing with DNA sequencing and MLPA. Among 141 limb movement disorders children, 75 cases were SMA. 71 cases of SMA (94.67 %) were with SMN c.840 mutation, 9 cases (12 %) with NAIP deletion and 3 cases (4 %) with GTF2H2 deletion. The multiple real-time PCR was able to diagnose and predict the prognosis of SMA patients. Simultaneously, the real-time PCR was applied to detect trace DNA from DBS and able to make an early diagnosis of SMA. CONCLUSION: The clinical and molecular characteristics of SMA in Southwest of China were presented. Our work provides a novel way for detecting SMA in children by using real-time PCR and the potential usage in newborn screening for early diagnosis of SMA.


Assuntos
Atrofia Muscular Espinal/diagnóstico , Atrofia Muscular Espinal/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Criança , Pré-Escolar , China , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Triagem Neonatal/métodos , Proteínas do Tecido Nervoso/genética , Proteína Inibidora de Apoptose Neuronal/genética , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Fatores de Transcrição/genética
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