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1.
Proc Natl Acad Sci U S A ; 121(11): e2312136121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38446848

RESUMO

Anxiety is a remarkably common condition among patients with pharyngitis, but the relationship between these disorders has received little research attention, and the underlying neural mechanisms remain unknown. Here, we show that the densely innervated pharynx transmits signals induced by pharyngeal inflammation to glossopharyngeal and vagal sensory neurons of the nodose/jugular/petrosal (NJP) superganglia in mice. Specifically, the NJP superganglia project to norepinephrinergic neurons in the nucleus of the solitary tract (NTSNE). These NTSNE neurons project to the ventral bed nucleus of the stria terminalis (vBNST) that induces anxiety-like behaviors in a murine model of pharyngeal inflammation. Inhibiting this pharynx→NJP→NTSNE→vBNST circuit can alleviate anxiety-like behaviors associated with pharyngeal inflammation. This study thus defines a pharynx-to-brain axis that mechanistically links pharyngeal inflammation and emotional response.


Assuntos
Faringite , Faringe , Humanos , Animais , Camundongos , Ansiedade , Encéfalo , Células Receptoras Sensoriais , Inflamação
2.
Plant Cell ; 35(6): 1970-1983, 2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-36945740

RESUMO

The utilization of stabilized DELLA proteins Rht-B1b and Rht-D1b was crucial for increasing wheat (Triticum aestivum) productivity during the Green Revolution. However, the underlying mechanisms remain to be clarified. Here, we cloned a gain-of-function allele of the GSK3/SHAGGY-like kinase-encoding gene GSK3 by characterizing a dwarf wheat mutant. Furthermore, we determined that GSK3 interacts with and phosphorylates the Green Revolution protein Rht-B1b to promote it to reduce plant height in wheat. Specifically, phosphorylation by GSK3 may enhance the activity and stability of Rht-B1b, allowing it to inhibit the activities of its target transcription factors. Taken together, we reveal a positive regulatory mechanism for the Green Revolution protein Rht-B1b by GSK3, which might have contributed to the Green Revolution in wheat.


Assuntos
Proteínas de Plantas , Triticum , Triticum/genética , Triticum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Alelos
3.
Plant J ; 119(1): 478-489, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38659310

RESUMO

The Q transcription factor plays important roles in improving multiple wheat domestication traits such as spike architecture, threshability and rachis fragility. However, whether and how it regulates abiotic stress adaptation remain unclear. We found that the transcriptional expression of Q can be induced by NaCl and abscisic acid treatments. Using the q mutants generated by CRISPR/Cas9 and Q overexpression transgenic lines, we showed that the domesticated Q gene causes a penalty in wheat salt tolerance. Then, we demonstrated that Q directly represses the transcription of TaSOS1-3B and reactive oxygen species (ROS) scavenging genes to regulate Na+ and ROS homeostasis in wheat. Furthermore, we showed that wheat salt tolerance protein TaWD40 interacts with Q to competitively interfere with the interaction between Q and the transcriptional co-repressor TaTPL. Taken together, our findings reveal that Q directly represses the expression of TaSOS1 and some ROS scavenging genes, thus causing a harmful effect on wheat salt tolerance.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio , Tolerância ao Sal , Triticum , Triticum/genética , Triticum/fisiologia , Triticum/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tolerância ao Sal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia
4.
EMBO J ; 40(1): e104615, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33280146

RESUMO

The BRASSINAZOLE-RESISTANT 1 (BZR1) transcription factor family plays an essential role in plant brassinosteroid (BR) signaling, but the signaling mechanism through which BZR1 and its homologs cooperate with certain coactivators to facilitate transcription of target genes remains incompletely understood. In this study, we used an efficient protein interaction screening system to identify blue-light inhibitor of cryptochromes 1 (BIC1) as a new BZR1-interacting protein in Arabidopsis thaliana. We show that BIC1 positively regulates BR signaling and acts as a transcriptional coactivator for BZR1-dependent activation of BR-responsive genes. Simultaneously, BIC1 interacts with the transcription factor PIF4 to synergistically and interdependently activate expression of downstream genes including PIF4 itself, and to promote plant growth. Chromatin immunoprecipitation assays demonstrate that BIC1 and BZR1/PIF4 interdependently associate with the promoters of common target genes. In addition, we show that the interaction between BIC1 and BZR1 is evolutionally conserved in the model monocot plant Triticum aestivum (bread wheat). Together, our results reveal mechanistic details of BR signaling mediated by a transcriptional activation module BIC1/BZR1/PIF4 and thus provide new insights into the molecular mechanisms underlying the integration of BR and light signaling in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Criptocromos/metabolismo , Transdução de Sinais/genética , Transcrição Gênica/genética , Ativação Transcricional/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Imunoprecipitação da Cromatina/métodos , Regulação da Expressão Gênica de Plantas/genética , Luz , Desenvolvimento Vegetal/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo
5.
New Phytol ; 242(6): 2524-2540, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38641854

RESUMO

Leaf senescence is a complex process strictly regulated by various external and endogenous factors. However, the key signaling pathway mediating leaf senescence remains unknown. Here, we show that Arabidopsis SPX1/2 negatively regulate leaf senescence genetically downstream of the strigolactone (SL) pathway. We demonstrate that the SL receptor AtD14 and MAX2 mediate the age-dependent degradation of SPX1/2. Intriguingly, we uncover an age-dependent accumulation of SLs in leaves via transcriptional activation of SL biosynthetic genes by the transcription factors (TFs) SPL9/15. Furthermore, we reveal that SPX1/2 interact with the WRKY75 subclade TFs to inhibit their DNA-binding ability and thus repress transcriptional activation of salicylic acid (SA) biosynthetic gene SA Induction-Deficient 2, gating the age-dependent SA accumulation in leaves at the leaf senescence onset stage. Collectively, our new findings reveal a signaling pathway mediating sequential activation of SL and salicylate biosynthesis for the onset of leaf senescence in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Lactonas , Folhas de Planta , Senescência Vegetal , Fatores de Transcrição , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Lactonas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Ácido Salicílico/metabolismo , Salicilatos/metabolismo , Transdução de Sinais , Ligação Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Vias Biossintéticas/efeitos dos fármacos , Vias Biossintéticas/genética
6.
Plant Physiol ; 193(2): 1580-1596, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37335918

RESUMO

Brassinosteroids play an essential role in promoting skotomorphogenesis, yet the underlying mechanisms remain unknown. Here we report that a plant-specific BLISTER (BLI) protein functions as a positive regulator of both BR signaling and skotomorphogenesis in Arabidopsis (Arabidopsis thaliana). We found that the glycogen synthase kinase 3 (GSK3)-like kinase BRASSINOSTEROID INSENSITIVE2 interacts with and phosphorylates BLI at 4 phosphorylation sites (Ser70, Ser146, Thr256, and Ser267) for degradation; in turn, BR inhibits degradation of BLI. Specifically, BLI cooperates with the BRASSINAZOLE RESISTANT1 (BZR1) transcription factor to facilitate the transcriptional activation of BR-responsive genes. Genetic analyses indicated that BLI is essentially required for BZR1-mediated hypocotyl elongation in the dark. Intriguingly, we reveal that BLI and BZR1 orchestrate the transcriptional expression of gibberellin (GA) biosynthetic genes to promote the production of bioactive GAs. Our results demonstrate that BLI acts as an essential regulator of Arabidopsis skotomorphogenesis by promoting BR signaling and GA biosynthesis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fosforilação , Quinase 3 da Glicogênio Sintase/genética , Brassinosteroides/metabolismo , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas Quinases/genética , Proteínas Quinases/metabolismo
7.
Physiol Plant ; 176(2): e14301, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38629128

RESUMO

Salt stress is one of the major factors that limits rice production. Therefore, identification of salt-tolerant alleles from wild rice is important for rice breeding. In this study, we constructed a set of chromosome segment substitution lines (CSSLs) using wild rice as the donor parent and cultivated rice Nipponbare (Nip) as the recurrent parent. Salt tolerance germinability (STG) was evaluated, and its association with genotypes was determined using this CSSL population. We identified 17 QTLs related to STG. By integrating the transcriptome and genome data, four candidate genes were identified, including the previously reported AGO2 and WRKY53. Compared with Nip, wild rice AGO2 has a structure variation in its promoter region and the expression levels were upregulated under salt treatments; wild rice WRKY53 also has natural variation in its promoter region, and the expression levels were downregulated under salt treatments. Wild rice AGO2 and WRKY53 alleles have combined effects for improving salt tolerance at the germination stage. One CSSL line, CSSL118 that harbors these two alleles was selected. Compared with the background parent Nip, CSSL118 showed comprehensive salt tolerance and higher yield, with improved transcript levels of reactive oxygen species scavenging genes. Our results provided promising genes and germplasm resources for future rice salt tolerance breeding.


Assuntos
Genes de Plantas , Oryza , Melhoramento Vegetal , Tolerância ao Sal , Oryza/anatomia & histologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Tolerância ao Sal/genética , Cromossomos de Plantas/genética , Alelos , Melhoramento Vegetal/métodos , Locos de Características Quantitativas/genética , Genótipo , Transcriptoma , Genoma de Planta/genética , Regiões Promotoras Genéticas , Regulação da Expressão Gênica de Plantas , Germinação , Brotos de Planta , Raízes de Plantas , Técnicas de Genotipagem , Polimorfismo Genético , Fenótipo
8.
Eur Arch Otorhinolaryngol ; 281(5): 2275-2280, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38085307

RESUMO

OBJECTIVES: To investigate the incidence and characteristics of adult otitis media with effusion (OME) before, during, and after the COVID-19 pandemic. METHODS: A retrospective descriptive study was conducted. The incidence, age, sex, affected ear side, time of OME onset according to COVID-19 and days of improvement after conservative treatment were determined to assess the clinical features of adult OME in different periods of the COVID-19 pandemic. RESULTS: The incidence of adult OME during these periods was 3.17%, 2.30%, 6.18%, and 3.68%, respectively. Unilateral ear involvement and male sex were more common. The onset of adult OME occurred 7.80 ± 3.97 days after COVID-19 diagnosis, and improvement was observed after 12.24 ± 5.08 days of conservative treatment. Patients in the post-pandemic period were older than those in the non-pandemic period. CONCLUSION: The incidence of adult OME in China showed a tendency to decrease, recover, and decrease again following the COVID-19 outbreak. Pandemic prevention and control measures have had a certain impact on reducing the incidence, but the elderly are more prone to this disease.


Assuntos
COVID-19 , Otite Média com Derrame , Adulto , Humanos , Masculino , Idoso , Recém-Nascido , Otite Média com Derrame/cirurgia , Pandemias , Estudos Retrospectivos , Incidência , Teste para COVID-19 , COVID-19/epidemiologia
9.
Eur Arch Otorhinolaryngol ; 281(4): 1735-1743, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37924365

RESUMO

PURPOSE: To investigate the effect of the interval between bilateral cochlear implantation on the development of bilateral peripheral auditory pathways as revealed by the electrically evoked auditory brainstem response (EABR). METHODS: Fifty-eight children with profound bilateral sensorineural hearing loss were recruited. Among them, 33 children received sequential bilateral cochlear implants (CIs), and 25 children received simultaneous bilateral CIs. The bilateral EABRs evoked by electrical stimulation from the CI electrode were recorded on the day of second-side CI activation. RESULTS: The latencies of wave III (eIII) and wave V (eV) were significantly shorter on the first CI side than on the second CI side in children with sequential bilateral CIs but were similar between the two sides in children with simultaneous bilateral CIs. Furthermore, the latencies were prolonged from apical to basal channels along the cochlea in the two groups. In children with sequential CIs, the inter-implant interval was negatively correlated with the eV latency on the first CI side and was positively correlated with bilateral differences in the eIII and eV latencies. CONCLUSIONS: Unilateral CI use promotes the maturation of ipsilateral auditory conduction function. However, a longer inter-implant interval results in more unbalanced development of bilateral auditory brainstem pathways. Bilateral cochlear implantation with no or a short interval is recommended.


Assuntos
Implante Coclear , Implantes Cocleares , Surdez , Perda Auditiva Neurossensorial , Criança , Humanos , Perda Auditiva Neurossensorial/cirurgia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Tronco Encefálico/cirurgia , Surdez/cirurgia
10.
Plant J ; 110(2): 325-336, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35181968

RESUMO

Fruit spine is an important agronomic trait in cucumber and the "numerous spines (ns)" cucumber varieties are popular in Europe and West Asia. Although the classical genetic locus of ns was reported more than two decades ago, the NS gene has not been cloned yet. In this study, nine genetic loci for the different densities of fruit spines were identified by a genome-wide association study. Among the nine loci, fsdG2.1 was closely associated with the classical genetic locus ns, which harbors a candidate gene Csa2G264590. Overexpression of Csa2G264590 resulted in lower fruit spine density, and the knockout mutant generated by CRISPR/Cas9 displayed an increased spine density, demonstrating that the Csa2G264590 gene is NS. NS is specifically expressed in the fruit peel and spine. Genetic analysis showed that NS regulates fruit spine development independently of the tuberculate gene, Tu, which regulates spine development on tubercules; the cucumber glabrous mutants csgl1 and csgl3 are epistatic to ns. Furthermore, we found that auxin levels in the fruit peel and spine were significantly lower in the knockout mutant ns-cr. Moreover, RNA-sequencing showed that the plant hormone signal transduction pathway was enriched. Notably, most of the auxin responsive Aux/IAA family genes were downregulated in ns-cr. Haplotype analysis showed that the non-functional haplotype of NS exists exclusively in the Eurasian cucumber backgrounds. Taken together, the cloning of NS gene provides new insights into the regulatory network of fruit spine development.


Assuntos
Cucumis sativus , Cucumis sativus/metabolismo , Frutas/metabolismo , Estudo de Associação Genômica Ampla , Ácidos Indolacéticos/metabolismo , Fenótipo , Proteínas de Plantas/metabolismo
11.
J Am Chem Soc ; 145(13): 7113-7122, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36951270

RESUMO

Cobalt-based catalysts have been widely used for Fischer-Tropsch synthesis (FTS) in industry; however, achieving rational catalyst design at the atomic level and thereby a higher activity and more long-chain-hydrocarbon products simultaneously remain an attractive and difficult challenge. The dual-atomic-site catalysts with unique electronic and geometric interface interactions offer a great opportunity for exploiting advanced FTS catalysts with improved performance. Herein, we designed a Ru1Zr1/Co catalyst with Ru and Zr dual atomic sites on the Co nanoparticle (NP) surface through a metal-organic-framework-mediated synthesis strategy which presents greatly enhanced FTS activity (high turnover frequency of 3.8 × 10-2 s-1 at 200 °C) and C5+ selectivity (80.7%). Control experiments presented a synergic effect between Ru and Zr single-atom site on Co NPs. Further density functional theory calculations of the chain growth process from C1 to C5 revealed that the designed Ru/Zr dual sites remarkably lower the rate-limiting barriers due to the significantly weakened C-O bond and promote the chain growth processes, resulting in the greatly boosted FTS performance. Therefore, our work demonstrates the effectiveness of dual-atomic-site design in promoting the FTS performance and provides new opportunities for developing efficient industrial catalysts.

12.
Small ; 19(10): e2206052, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36549675

RESUMO

Precisely controlling the selectivity of nanocatalysts has always been a hot topic in heterogeneous catalysis but remains difficult owing to their complex and inhomogeneous catalytic sites. Herein, an effective strategy to regulate the chemoselectivity of Pd nanocatalysts for selective hydrogenation reactions by inserting single-atom Zn into Pd nanoparticles is reported. Taking advantage of the tannic acid coating-confinement strategy, small-sized Pd nanoparticles with inserted single-atom Zn are obtained on the O-doped carbon-coated alumina. Compared with the pure Pd nanocatalyst, the Pd nanocatalyst with single-atom Zn insertion exhibits prominent selectivity for the hydrogenation of p-iodonitrobenzene to afford the hydrodeiodination product instead of nitro hydrogenation ones. Further computational studies reveal that the single-atom Zn on Pd nanoparticles strengthens the adsorption of the nitro group to avoid its reduction and increases the d-band center of Pd atoms to facilitate the reduction of the iodo group, which leads to enhanced selectivity. This work provides new guidelines to tune the selectivity of nanocatalysts with guest single-atom sites.

13.
New Phytol ; 239(3): 920-935, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37209253

RESUMO

Drought stress causes substantial losses in crop production per year worldwide, threatening global food security. Identification of the genetic components underlying drought tolerance in plants is of great importance. In this study, we report that loss-of-function of the chromatin-remodeling factor PICKLE (PKL), which is involved in repression of transcription, enhances drought tolerance of Arabidopsis. At first, we find that PKL interacts with ABI5 to regulate seed germination, but PKL regulates drought tolerance independently of ABI5. Then, we find that PKL is necessary for repressing the drought-tolerant gene AFL1, which is responsible for the drought-tolerant phenotype of pkl mutant. Genetic complementation tests demonstrate that the Chromo domain and ATPase domain but not the PHD domain are required for the function of PKL in regulating drought tolerance. Interestingly, we find that the DNA-binding domain (DBD) is essential for the protein stability of PKL. Furthermore, we demonstrate that the SUMO E3 ligase MMS21 interacts with and enhances the protein stability of PKL. Genetic interaction analysis shows that MMS21 and PKL additively regulate plant drought tolerance. Collectively, our findings uncover a MMS21-PKL-AFL1 module in regulating plant drought tolerance and offer insights into a novel strategy to improve crop drought tolerance.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Resistência à Seca , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Secas , Regulação da Expressão Gênica de Plantas
14.
J Integr Plant Biol ; 65(12): 2552-2568, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37811725

RESUMO

Low-temperature (LT) stress threatens cucumber production globally; however, the molecular mechanisms underlying LT tolerance in cucumber remain largely unknown. Here, using a genome-wide association study (GWAS), we found a naturally occurring single nucleotide polymorphism (SNP) in the STAYGREEN (CsSGR) coding region at the gLTT5.1 locus associated with LT tolerance. Knockout mutants of CsSGR generated by clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR-associated nuclease 9 exhibit enhanced LT tolerance, in particularly, increased chlorophyll (Chl) content and reduced reactive oxygen species (ROS) accumulation in response to LT. Moreover, the C-repeat Binding Factor 1 (CsCBF1) transcription factor can directly activate the expression of CsSGR. We demonstrate that the LT-sensitive haplotype CsSGRHapA , but not the LT-tolerant haplotype CsSGRHapG could interact with NON-YELLOW COLORING 1 (CsNYC1) to mediate Chl degradation. Geographic distribution of the CsSGR haplotypes indicated that the CsSGRHapG was selected in cucumber accessions from high latitudes, potentially contributing to LT tolerance during cucumber cold-adaptation in these regions. CsSGR mutants also showed enhanced tolerance to salinity, water deficit, and Pseudoperonospora cubensis, thus CsSGR is an elite target gene for breeding cucumber varieties with broad-spectrum stress tolerance. Collectively, our findings provide new insights into LT tolerance and will ultimately facilitate cucumber molecular breeding.


Assuntos
Cucumis sativus , Cucumis sativus/genética , Temperatura , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Temperatura Baixa
15.
New Phytol ; 233(3): 1414-1425, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34800046

RESUMO

Tillering is an important parameter of plant architecture in cereal crops. In this study, we identified the PHYTOCHROME-INTERACTING FACTOR-LIKE (PIL) family transcription factors as new repressors of tillering in cereal crops. Using biochemical and genetic approaches, we explore the roles of TaPIL1 in regulating wheat plant architecture. We found that the PIL protein TaPIL1 controls tiller number in wheat. Overexpression of TaPIL1 reduces wheat tiller number; additionally, overexpression of TaPIL1-SUPERMAN repression domain increases wheat tiller number. Furthermore, we show that TaPIL1 activates the transcriptional expression of wheat TEOSINTE BRANCHED1 (TaTB1); moreover, TaPIL1 physically interacts with wheat SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (TaSPL)3/17, which are activators of TaTB1 transcription. In rice, overexpression and loss-of-function mutations of OsPIL11 reduce or increase tiller number by regulating the expression of OsTB1. In Arabidopsis, we demonstrate that PHYTOCHROME-INTERACTING FACTOR 4 interacts with SPL9 to inhibit shoot branching. This study reveals that PIL family transcription factors directly interact with SPLs and play an important role in repressing tillering/branching in plants.


Assuntos
Oryza , Fitocromo , Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Fitocromo/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Theor Appl Genet ; 135(8): 2593-2607, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35764690

RESUMO

KEY MESSAGE: The CsGAI gene, identified by map-based, was involved in regulating seed germination in low temperature via the GA and ABA signaling pathways. Low temperature reduces the percentage of seeds germinating and delays seed germinating time, thus posing a threat to cucumber production. However, the molecular mechanism regulating low temperature germination in cucumber is unknown. We here dissected a major quantitative trait locus qLTG1.1 that controls seed germination at low temperature in cucumber. First, we fine-mapped qLTG1.1 to a 46.3-kb interval, containing three candidate genes. Sequence alignment and gene expression analysis identified Csa1G408720 as the gene of interest that was highly expressed in seeds, and encoded a highly conserved, low temperature-regulated DELLA family protein CsGAI. GUS expression analysis indicated that higher promoter activity underscored higher transcriptional expression of the CsGAI gene. Consistent with the known roles of GAI in ABA and GA signaling during germination, genes involved in the GA (CsGA2ox, CsGA3ox) and ABA biosynthetic pathways (CsABA1, CsABA2, CsAAO3 and CsNCED) were found to be differently regulated in the tolerant and sensitive genotypes under low temperatures, and this was reflected in differences in their ratio of GA-to-ABA. Based on these data, we proposed a working model explaining how CsGAI integrates the GA and ABA signaling pathways, to regulate cucumber seed germination at low temperature, thus providing new insights into this mechanism.


Assuntos
Cucumis sativus , Germinação , Ácido Abscísico/metabolismo , Cucumis sativus/genética , Cucumis sativus/metabolismo , Regulação da Expressão Gênica de Plantas , Germinação/genética , Giberelinas/metabolismo , Sementes/metabolismo , Temperatura
17.
Eur Arch Otorhinolaryngol ; 279(10): 4847-4852, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35247096

RESUMO

PURPOSE: To investigate the auditory pathway functions in deaf patients with Mondini malformation using the electrically evoked auditory brainstem response (EABR) during cochlear implantation (CI). METHODS: A total of 58 patients with severe to profound sensorineural hearing loss (SNHL) were included in this study. Of these patients, 27 cases had Mondini malformation and 31 control cases had no inner ear malformations (IEMs). Intraoperative EABRs evoked by electrical stimulation at the round window niche (RWN) and round window membrane (RWM) were recorded. RESULTS: Patients with Mondini malformation showed significantly lower EABR extraction rates than those with no IEMs did. However, for patients who showed EABRs, no significant difference in EABR thresholds, wave III (eIII) latencies, wave V (eV) latencies or eIII-eV latency intervals was found between two groups. CONCLUSION: The physiological functions of the peripheral auditory system in patients with Mondini malformation may divide into opposite extremes, as revealed by a robust EABR and the absence of the EABR, respectively. The auditory conduction function should be objectively and individually evaluated for patients with Mondini malformation by the EABR.


Assuntos
Implante Coclear , Implantes Cocleares , Perda Auditiva Neurossensorial , Limiar Auditivo , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Feminino , Audição , Perda Auditiva Neurossensorial/cirurgia , Humanos , Gravidez
18.
New Phytol ; 230(3): 988-1002, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33521967

RESUMO

The domestication gene Q is largely responsible for the widespread cultivation of wheat because it confers multiple domestication traits. However, the underlying molecular mechanisms of how Q regulates these domestication traits remain unclear. In this study, we identify a Q-interacting protein TaLAX1, a basic helix-loop-helix transcription factor, through yeast two-hybrid assays. Using biochemical and genetic approaches, we explore the roles of TaLAX1 in regulating wheat domestication traits. Overexpression of TaLAX1 produces phenotypes, reminiscent of the q allele; loss-of-function Talax1 mutations confer compact spikes, largely similar to the Q-overexpression wheat lines. The two transcription factors TaLAX1 and Q disturb each other's activity to antagonistically regulate the expression of the lignin biosynthesis-related gene TaKNAT7-4D. More interestingly, a natural variation (InDel, +/- TATA), which occurs in the promoter of TaLAX1, is associated with the promoter activity difference between the D subgenome of bread wheat and its ancestor Aegilops tauschii accession T093. This study reveals that the transcription factor TaLAX1 physically interacts with Q to antagonistically regulate wheat domestication traits and a natural variation (InDel, +/- TATA) is associated with the diversification of TaLAX1 promoter activity.


Assuntos
Fatores de Transcrição , Triticum , Pão , Grão Comestível , Morfogênese , Fatores de Transcrição/genética , Triticum/genética
19.
J Exp Bot ; 72(8): 2857-2876, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33471899

RESUMO

With the growth of the global population and the increasing frequency of natural disasters, crop yields must be steadily increased to enhance human adaptability to risks. Pre-harvest sprouting (PHS), a term mainly used to describe the phenomenon in which grains germinate on the mother plant directly before harvest, is a serious global problem for agricultural production. After domestication, the dormancy level of cultivated crops was generally lower than that of their wild ancestors. Although the shortened dormancy period likely improved the industrial performance of cereals such as wheat, barley, rice, and maize, the excessive germination rate has caused frequent PHS in areas with higher rainfall, resulting in great economic losses. Here, we systematically review the causes of PHS and its consequences, the major indicators and methods for PHS assessment, and emphasize the biological significance of PHS in crop production. Wheat quantitative trait loci functioning in the control of PHS are also comprehensively summarized in a meta-analysis. Finally, we use Arabidopsis as a model plant to develop more complete PHS regulatory networks for wheat. The integration of this information is conducive to the development of custom-made cultivated lines suitable for different demands and regions, and is of great significance for improving crop yields and economic benefits.


Assuntos
Grão Comestível , Oryza , Grão Comestível/genética , Germinação , Oryza/genética , Dormência de Plantas , Locos de Características Quantitativas/genética , Triticum/genética
20.
Nanotechnology ; 32(50)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34547735

RESUMO

Visible light-driven photoreduction of CO2and H2O to tunable syngas is an appealing strategy for both artificial carbon neutral and Fischer-Tropsch processes. However, the development of photocatalysts with high activity and selectivity remains challenging. For this case, we here design a hybrid catalyst, synthesized byin situdeposition of Ag crystals on GaN nanobelts, that delivers a tunable H2/CO ratio between 0.5 and 3 under visible light irradiation (λ > 400 nm). The obtained photocatalyst delivers a maximal turnover frequency value of 3.85 h-1and a corresponding yield rate of 2.12 mmol h-1g-1for CO production, while the photocatalytic activity keeps stable during five cycling tests. Additionally, syngas can be detected even atλ > 600 nm. Experiments and mechanistic studies reveal that the existence of Ag crystals not only extends the light absorption region but also promotes the charge transfer efficiency, and thereby leading to a photocatalytic improvement. Accordingly, the present work affords an opportunity for developing an efficient photo-driven system by using solar energy to alleviate CO2emissions.

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