RESUMO
Extracellular perception of auxin, an essential phytohormone in plants, has been debated for decades. Auxin-binding protein 1 (ABP1) physically interacts with quintessential transmembrane kinases (TMKs) and was proposed to act as an extracellular auxin receptor, but its role was disputed because abp1 knockout mutants lack obvious morphological phenotypes. Here, we identified two new auxin-binding proteins, ABL1 and ABL2, that are localized to the apoplast and directly interact with the extracellular domain of TMKs in an auxin-dependent manner. Furthermore, functionally redundant ABL1 and ABL2 genetically interact with TMKs and exhibit functions that overlap with those of ABP1 as well as being independent of ABP1. Importantly, the extracellular domain of TMK1 itself binds auxin and synergizes with either ABP1 or ABL1 in auxin binding. Thus, our findings discovered auxin receptors ABL1 and ABL2 having functions overlapping with but distinct from ABP1 and acting together with TMKs as co-receptors for extracellular auxin.
Assuntos
Arabidopsis , Ácidos Indolacéticos , Reguladores de Crescimento de Plantas , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/química , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismoRESUMO
The phytohormone auxin controls many processes in plants, at least in part through its regulation of cell expansion1. The acid growth hypothesis has been proposed to explain auxin-stimulated cell expansion for five decades, but the mechanism that underlies auxin-induced cell-wall acidification is poorly characterized. Auxin induces the phosphorylation and activation of the plasma membrane H+-ATPase that pumps protons into the apoplast2, yet how auxin activates its phosphorylation remains unclear. Here we show that the transmembrane kinase (TMK) auxin-signalling proteins interact with plasma membrane H+-ATPases, inducing their phosphorylation, and thereby promoting cell-wall acidification and hypocotyl cell elongation in Arabidopsis. Auxin induced interactions between TMKs and H+-ATPases in the plasma membrane within seconds, as well as TMK-dependent phosphorylation of the penultimate threonine residue on the H+-ATPases. Our genetic, biochemical and molecular evidence demonstrates that TMKs directly phosphorylate plasma membrane H+-ATPase and are required for auxin-induced H+-ATPase activation, apoplastic acidification and cell expansion. Thus, our findings reveal a crucial connection between auxin and plasma membrane H+-ATPase activation in regulating apoplastic pH changes and cell expansion through TMK-based cell surface auxin signalling.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Membrana Celular/metabolismo , Parede Celular/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Ácidos , Arabidopsis/citologia , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Membrana Celular/enzimologia , Ativação Enzimática , Concentração de Íons de Hidrogênio , Hipocótilo/enzimologia , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/metabolismo , Proteínas de Membrana/genética , Fosforilação , Reguladores de Crescimento de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , ATPases Translocadoras de Prótons/química , ATPases Translocadoras de Prótons/metabolismo , Prótons , Treonina/metabolismoRESUMO
The plant hormone auxin plays a key role to maintain root stem cell identity which is essential for root development. However, the molecular mechanism by which auxin regulates root distal stem cell (DSC) identity is not well understood. In this study, we revealed that the cell cycle factor DPa is a vital regulator in the maintenance of root DSC identity through multiple auxin signaling cascades. On the one hand, auxin positively regulates the transcription of DPa via AUXIN RESPONSE FACTOR 7 and ARF19. On the other hand, auxin enhances the protein stability of DPa through MITOGEN-ACTIVATED PROTEIN KINASE 3 (MPK3)/MPK6-mediated phosphorylation. Consistently, mutation of the identified three threonine residues (Thr10, Thr25, and Thr227) of DPa to nonphosphorylated form alanine (DPa3A) highly decreased the phosphorylation level of DPa, which decreased its protein stability and affected the maintenance of root DSC identity. Taken together, this study provides insight into the molecular mechanism of how auxin regulates root distal stem cell identity through the dual regulations of DPa at both transcriptional and posttranslational levels.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Divisão Celular , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Raízes de Plantas/metabolismo , Células-Tronco/metabolismoRESUMO
The formation of cell polarity is essential for many developmental processes such as polar cell growth and spatial patterning of cell division. A plant-specific ROP (Rho-like GTPases from Plants) subfamily of conserved Rho GTPase plays a crucial role in the regulation of cell polarity. However, the functional study of ROPs in angiosperm is challenging because of their functional redundancy. The Marchantia polymorpha genome encodes a single ROP gene, MpROP, providing an excellent genetic system to study ROP-dependent signaling pathways. Mprop knockout mutants exhibited rhizoid growth defects, and MpROP was localized at the tip of elongating rhizoids, establishing a role for MpROP in the control of polar cell growth and its functional conservation in plants. Furthermore, the Mprop knockout mutant showed defects in the formation of meristem notches associated with disorganized cell division patterns. These results reveal a critical function of MpROP in the regulation of plant development. Interestingly, these phenotypes were complemented not only by MpROP but also Arabidopsis AtROP2, supporting the conservation of ROP's function among land plants. Our results demonstrate a great potential for M. polymorpha as a powerful genetic system for functional and mechanistic elucidation of ROP signaling pathways during plant development.
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Proteínas de Arabidopsis , Arabidopsis , Marchantia , Meristema/genética , Meristema/metabolismo , Arabidopsis/metabolismo , Marchantia/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Divisão Celular/genética , Plantas/metabolismoRESUMO
BACKGROUND: Significant individual differences exist in the insight of patients with obsessive-compulsive disorder (OCD), and the clinical characteristics of OCD patients with varying levels of insight are not entirely uniform. This study aims to investigate disparities in disease severity, anxiety, and depression status among OCD patients with differing levels of insight, with the goal of generating novel treatment strategies for OCD. METHODS: A total of 114 patients diagnosed with OCD were recruited from the Department of Psychology at Affiliated Mental Health Center & Hangzhou Seventh People's Hospital to participate in this research. Based on their Total Insight and Treatment Attitude Questionnaire (ITAQ) scores, the patients were divided into two groups: Group OCD with high insight (referred to as Group OCD-HI, ITAQ score ≥20 points, n = 80) and Group OCD with low insight (referred to as Group OCD-LI, ITAQ score <20 points, n = 34). Subsequently, the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Hamilton Anxiety Scale (HAMA), and Hamilton Depression Scale (HAMD) scores were compared between the two groups. All questionnaires for this study were completed by experienced psychiatrists. RESULTS: The Y-BOCS scores for YB1, YB2, YB4, YB5, YB6, YB9, and the total Y-BOCS scores in Group OCD-HI were significantly higher than those in Group OCD-LI (p < 0.05). Conversely, Group OCD-HI exhibited significantly lower HAMA and HAMD scores compared to Group OCD-LI (p < 0.05). Furthermore, the total ITAQ score displayed a significant negative correlation with the total Y-BOCS, HAMA, and HAMD scores (p < 0.05). CONCLUSIONS: This study revealed that certain OCD patients exhibit incomplete insight, and this lack of insight is strongly associated with increased disease severity and heightened levels of anxiety and depression. It is hoped that by enhancing the insight of OCD patients, the goal of ameliorating disease symptoms and alleviating negative emotions can be attained.
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Depressão , Transtorno Obsessivo-Compulsivo , Humanos , Transtorno Obsessivo-Compulsivo/complicações , Transtorno Obsessivo-Compulsivo/diagnóstico , Transtornos de Ansiedade , Ansiedade , Gravidade do PacienteRESUMO
BACKGROUND: Type 2 diabetes mellitus (T2DM) induced diabetes-associated cognitive dysfunction (DACD) that seriously affects the self-management of T2DM patients, is currently one of the most severe T2DM-associated complications, but the mechanistic basis remains unclear. Mitochondria are highly dynamic organelles, whose function refers to a broad spectrum of features such as mitochondrial dynamics, mitophagy and so on. Mitochondrial abnormalities have emerged as key determinants for cognitive function, the relationship between DACD and mitochondria is not well understood. METHODS: Here, we explored the underlying mechanism of mitochondrial dysfunction of T2DM mice and HT22 cells treated with high glucose/palmitic acid (HG/Pal) focusing on the mitochondrial fission-mitophagy axis with drug injection, western blotting, Immunofluorescence, and electron microscopy. We further explored the potential role of caveolin-1 (cav-1) in T2DM induced mitochondrial dysfunction and synaptic alteration through viral transduction. RESULTS: As previously reported, T2DM condition significantly prompted hippocampal mitochondrial fission, whereas mitophagy was blocked rather than increasing, which was accompanied by dysfunctional mitochondria and impaired neuronal function. By contrast, Mdivi-1 (mitochondrial division inhibitor) and urolithin A (mitophagy activator) ameliorated mitochondrial and neuronal function and thereafter lead to cognitive improvement by inhibiting excessive mitochondrial fission and giving rise to mitophagy, respectively. We have previously shown that cav-1 can significantly improve DACD by inhibiting ferroptosis. Here, we further demonstrated that cav-1 could not only inhibit mitochondrial fission via the interaction with GSK3ß to modulate Drp1 pathway, but also rescue mitophagy through interacting with AMPK to activate PINK1/Parkin and ULK1-dependent signlings. CONCLUSIONS: Overall, our data for the first time point to a mitochondrial fission-mitophagy axis as a driver of neuronal dysfunction in a phenotype that was exaggerated by T2DM, and the protective role of cav-1 in DACD. Graphic Summary Illustration. In T2DM, excessive mitochondrial fission and impaired mitophagy conspire to an altered mitochondrial morphology and mitochondrial dysfunction, with a consequent neuronal damage, overall suggesting an unbalanced mitochondrial fission-mitophagy axis. Upon cav-1 overexpression, GSK3ß and AMPK are phosphorylated respectively to activate Drp1 and mitophagy-related pathways (PINK1 and ULKI), ultimately inhibits mitochondrial fission and enhances mitophagy. In the meantime, the mitochondrial morphology and neuronal function are rescued, indicating the protective role of cav-1 on mitochondrial fission-mitophagy axis. Video Abstract.
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Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Doenças Mitocondriais , Humanos , Camundongos , Animais , Mitofagia , Dinâmica Mitocondrial/genética , Diabetes Mellitus Tipo 2/complicações , Caveolina 1/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Neurônios/metabolismo , Disfunção Cognitiva/etiologia , Ubiquitina-Proteína Ligases/metabolismoRESUMO
We report the use of halogen bonding (XB) for the generation of aryl radicals from aryl halides under blue light irradiation and applied it in radical generation/1,5-hydrogen-atom transfer/radical cyclization cascade reactions for the synthesis of oxindoles and isoindolinones. On the basis of experimental studies, we propose that DBU can serve as a suitable XB acceptor with aryl halides for the formation of a photoactive electron donor and acceptor complex.
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Background: Obsessive-compulsive disorder (OCD) is frequently treated using a combination of counseling, drugs, and, more recently various transcranial stimulation protocols, but all require several weeks to months for clinically significant improvement, so there is a need for treatments with faster onset. This study investigated whether an accelerated high-dose theta burst stimulation (ahTBS) protocol significantly improves the efficacy of OCD compared to traditional 1-Hz repetitive transcranial magnetic stimulation (rTMS) in the routine clinical setting. Method: Forty-five patients with OCD were randomized into two groups and treated with ahTBS or 1-Hz rTMS for 5 days. Patients were assessed at baseline at the end of treatment using the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Results: After 5 days of treatment, there was a significant decrease in Y-BOCS scores in both groups (p < 0.001), and the difference between the two groups was not statistically significant (group × time interaction, F = 1.90, p=0.18). There was also no statistically significant difference in other secondary outcome indicators, including depression, anxiety symptoms, and response rate. However, the ahTBS group had a greater trend in response rate. Neuropsychological testing showed no negative cognitive side effects of either treatment. Conclusion: Accelerated high-dose TBS is as safe and has comparable short-term efficacy to traditional 1-Hz rTMS for the clinical treatment of OCD. Further research is needed to explore optimal ahTBS parameters, validate the utility of this treatment modality, and identify factors predictive of rapid clinical response to guide clinical decision-making. This trial is registered with NCT05221632.
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Transtorno Obsessivo-Compulsivo , Estimulação Magnética Transcraniana , Humanos , Estimulação Magnética Transcraniana/métodos , Projetos de Pesquisa , Transtorno Obsessivo-Compulsivo/terapia , Testes Neuropsicológicos , Resultado do TratamentoRESUMO
Diabetes-associated cognitive impairment (DACI) can increase the risk of major cardiovascular events and death. Neuronal functionality is highly dependent on mitochondria and emerging evidence has shown that mitochondrial transplantation is a potential and effective strategy that can reduce brain injury and associated disorders. Platelets are abundant in blood and can be considered a readily available source of small-size mitochondria. These cells can be easily acquired from the peripheral blood with minimal invasion via simple venipuncture. The present study aimed to investigate whether transplantation of platelet-derived mitochondria (Mito-Plt) could improve DACI. Cognitive behaviors were assessed using the Morris water maze test in db/db mice. The results demonstrated that Mito-Plt was internalized into hippocampal neurons 24 h following intracerebroventricular injection. Importantly, one month following Mito-Plt transplantation, DACI was alleviated in db/db mice and the effect was accompanied with increased mitochondrial number, restored mitochondrial function, attenuated oxidative stress and neuronal apoptosis, as well as decreased accumulation of Aß and Tau in the hippocampus. Taken together, the data demonstrated that transplantation of Mito-Plt attenuated cognitive impairment and mitochondrial dysfunction in db/db mice. This method may be a potential therapeutic application for the treatment of DACI.
Assuntos
Plaquetas/metabolismo , Disfunção Cognitiva/terapia , Diabetes Mellitus Tipo 2/metabolismo , Mitocôndrias/transplante , Animais , Apoptose , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Hipocampo/citologia , Hipocampo/metabolismo , Injeções Intraventriculares , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Neurônios/citologia , Neurônios/metabolismo , Ratos Sprague-Dawley , Transplante HeterólogoRESUMO
AIM AND BACKGROUND: Postoperative nausea and vomiting (PONV) remains a significant clinical problem for surgical patients. Amisulpride is a well-studied D2/D3 antagonist that has the potential to be used for preventing and treating PONV. Our aim was to assess the efficacy and safety of amisulpride for prevention and treatment of PONV through a systematic review and meta-analysis. METHOD: A systematic literature search was performed using MEDLINE, EMBASE, PUBMED, clinicaltrials.gov, and the Cochrane Central Register of Controlled Trials from their inception to Feb 15th, 2019. The efficacy outcome was the incidence of complete response, defined as no emesis and no rescue antiemetic use in a 24-h period after study drug administration. The safety outcomes were the adverse effects associated with amisulpride. RESULTS: Five studies comprising 3243 patients met inclusion critieria. Compared with placebo, amisulpride showed a significantly improved incidence of complete response [relative risk (RR): 1.30; 95% confidence interval (CI): 1.20-1.41; P < 0.00001, I2 = 0%] with firm evidence from the trial sequential analysis. Particularly, the amisulpride at 5 mg dose indicated a significant benefit than placebo [relative risk (RR): 1.28; 95% confidence interval (CI): 1.18-1.39; P < 0.00001, I2 = 4%]. The adverse event profile of amisulpride was generally similar to the placebo. CONCLUSION: Based on our findings, low-dose, intravenous amisulpride is safe and efficacious for the prevention and treatment of PONV compared to placebo. Further studies are needed to explore the optimal dose and timing. CLINICAL TRIAL REGISTRATION: PROSPERO: CRD42019121483.
Assuntos
Amissulprida/uso terapêutico , Antagonistas de Dopamina/uso terapêutico , Náusea e Vômito Pós-Operatórios/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
High-quality cotton fibre equates to a more comfortable textile. Fibre length is an important index of fibre quality. Hydrogen peroxide (H2O2) acts as a signalling molecule in the regulation of fibre elongation. Results from in vitro ovule culture suggest that the alteration of fibre cell H2O2 levels affects fibre development. Ascorbate peroxidase (APX) is an important reactive oxygen species (ROS) scavenging enzyme, and we found that GhAPX1AT/DT encoded one member of the previously unrealized group of cytosolic APXs (cAPXs) that were preferentially expressed during the fibre elongation stage. Transgenic cottons with up- and down-regulation of GhAPX1AT/DT were generated to control fibre endogenous levels of H2O2 Suppression of all cAPX (IAO) resulted in a 3.5-fold increase in H2O2 level in fibres and oxidative stress, which significantly suppressed fibre elongation. The fibre length of transgenic lines with over-expression or specific down-regulation of GhAPX1AT/DT did not show any obvious change. However, the fibres in the over-expression lines exhibited higher tolerance to oxidative stress. Differentially expressed genes (DEGs) in fibres at 10 days post-anthesis (DPA) of IAO lines identified by RNA-seq were related to redox homeostasis, signalling pathways, stress responses and cell wall synthesis, and the DEGs that were up-regulated in IAO lines were also up-regulated in the 10 DPA and 20 DPA fibres of wild cotton compared with domesticated cotton. These results suggest that optimal H2O2 levels and redox state regulated by cytosolic APX are key mechanisms regulating fibre elongation, and dysregulation of the increase in H2O2 induces oxidative stress and results in shorter fibres by initiating secondary cell wall-related gene expression.
Assuntos
Ascorbato Peroxidases/genética , Regulação da Expressão Gênica de Plantas , Gossypium/fisiologia , Proteínas de Plantas/genética , Ascorbato Peroxidases/metabolismo , Fibra de Algodão , Citosol/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Gossypium/enzimologia , Gossypium/genética , Gossypium/crescimento & desenvolvimento , Homeostase , Peróxido de Hidrogênio/farmacologia , Oxirredução , Filogenia , Proteínas de Plantas/metabolismoRESUMO
BACKGROUND: Accumulating evidence suggests that altered immunity contributes to the development of major depressive disorder (MDD). AIMS: To examine whether complement factor H (CFH), a regulator of activation of the alternative pathway of the complement cascade, confers susceptibility to MDD. METHOD: Expression analyses were tested in 53 unmedicated people with MDD and 55 healthy controls. A two-stage genetic association analysis was performed in 3323 Han Chinese with or without MDD. Potential associations between CFH single nucleotide polymorphisms and age at MDD onset were evaluated. RESULTS: CFH levels were significantly lower in the MDD group at both protein and mRNA levels (P = 0.009 and P = 0.014 respectively). A regulatory variant in the CFH gene, rs1061170, showed statistically significant genotypic and allelic differences between the MDD and control groups (genotypic P = 0.0005, allelic P = 0.0001). Kaplan-Meier survival analysis showed that age at onset of MDD was significantly associated with the C allele of rs1061170 (log rank statistic χ(2) = 6.82, P = 0.009). The C-allele carriers had a younger age at onset of MDD (22.2 years, s.d. = 4.0) than those without the C allele (23.6 years, s.d. = 4.3). CONCLUSIONS: CFH is likely to play an important role in the development of MDD. rs1061170 has an important effect on age at onset of MDD in Han Chinese and may therefore be related to early pathogenesis of MDD, although further study is needed.
Assuntos
Transtorno Depressivo Maior/genética , Adulto , Idade de Início , China , Fator H do Complemento/genética , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
microRNAs (miRNAs) are 20-24 nucleotide non-coding small RNAs that play important roles in plant development. The stages of cotton fiber development include initiation, elongation, secondary wall thickening (SWT) and maturation. We constructed seven fiber RNA libraries representing the initiation, elongation and SWT stages. In total, 47 conserved miRNA families and seven candidate miRNAs were profiled using small RNA sequencing. Northern blotting and real-time polymerase chain reaction (PCR) analyses revealed the dynamic expression of miRNAs during fiber development. In addition, 140 targets of 30 conserved miRNAs and 38 targets of five candidate miRNAs were identified through degradome sequencing. Analysis of correlated expression between miRNAs and their targets demonstrated that specific miRNAs suppressed the expression of transcription factors, SBP and MYB, a leucine-rich receptor-like protein kinase, a pectate lyase, α-tubulin, a UDP-glucuronic acid decarboxylase and cytochrome C oxidase subunit 1 to affect fiber development. Histochemical analyses detected the biological activity of miRNA156/157 in ovule and fiber development. Suppressing miRNA156/157 function resulted in the reduction of mature fiber length, illustrating that miRNA156/157 plays an essential role in fiber elongation.
Assuntos
Gossypium/genética , MicroRNAs/genética , RNA de Plantas/genética , Northern Blotting , Gossypium/crescimento & desenvolvimento , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Studies using animal models have shown that depression affects the stability of the microbiota, but the actual structure and composition in patients with major depressive disorder (MDD) are not well understood. Here, we analyzed fecal samples from 46 patients with depression (29 active-MDD and 17 responded-MDD) and 30 healthy controls (HCs). High-throughput pyrosequencing showed that, according to the Shannon index, increased fecal bacterial α-diversity was found in the active-MDD (A-MDD) vs. the HC group but not in the responded-MDD (R-MDD) vs. the HC group. Bacteroidetes, Proteobacteria, and Actinobacteria strongly increased in level, whereas that of Firmicutes was significantly reduced in the A-MDD and R-MDD groups compared with the HC group. Despite profound interindividual variability, levels of several predominant genera were significantly different between the MDD and HC groups. Most notably, the MDD groups had increased levels of Enterobacteriaceae and Alistipes but reduced levels of Faecalibacterium. A negative correlation was observed between Faecalibacterium and the severity of depressive symptoms. These findings enable a better understanding of changes in the fecal microbiota composition in such patients, showing either a predominance of some potentially harmful bacterial groups or a reduction in beneficial bacterial genera. Further studies are warranted to elucidate the temporal and causal relationships between gut microbiota and depression and to evaluate the suitability of the microbiome as a biomarker.
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Transtorno Depressivo Maior/microbiologia , Fezes/microbiologia , Microbiota/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Cotton fiber is a single cell that differentiates from the ovule epidermis and undergoes synchronous elongation with high secretion and growth rate. Apart from economic importance, cotton fiber provides an excellent single-celled model for studying mechanisms of cell-growth. Annexins are Ca(2+)- and phospholipid-binding proteins that have been reported to be localized in multiple cellular compartments and involved in control of vesicle secretions. Although several annexins have been found to be highly expressed in elongating cotton fibers, their functional roles in fiber development remain unknown. Here, 14 annexin family members were identified from the fully sequenced diploid G. raimondii (D5 genome), half of which were expressed in fibers of the cultivated tetraploid species G. hirsutum (cv. YZ1). Among them, GhAnn2 from the D genome of the tetraploid species displayed high expression level in elongating fiber. The expression of GhAnn2 could be induced by some phytohormones that play important roles in fiber elongation, such as IAA and GA3. RNAi-mediated down-regulation of GhAnn2 inhibited fiber elongation and secondary cell wall synthesis, resulting in shorter and thinner mature fibers in the transgenic plants. Measurement with non-invasive scanning ion-selective electrode revealed that the rate of Ca(2+) influx from extracellular to intracellular was decreased at the fiber cell apex of GhAnn2 silencing lines, in comparison to that in the wild type. These results indicate that GhAnn2 may regulate fiber development through modulating Ca(2+) fluxes and signaling.
Assuntos
Anexinas/fisiologia , Cálcio/metabolismo , Fibra de Algodão , Gossypium/citologia , Proteínas de Plantas/fisiologia , Anexinas/genética , Anexinas/metabolismo , Sinalização do Cálcio , Crescimento Celular , Regulação para Baixo , Etiquetas de Sequências Expressas , Gossypium/genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Interferência de RNA , Análise de SequênciaRESUMO
Fiber elongation is the key determinant of fiber quality and output in cotton (Gossypium hirsutum). Although expression profiling and functional genomics provide some data, the mechanism of fiber development is still not well understood. Here, a gene encoding a calcium sensor, GhCaM7, was isolated based on its high expression level relative to other GhCaMs in fiber cells at the fast elongation stage. The level of expression of GhCaM7 in the wild-type and the fuzzless/lintless mutant correspond to the presence and absence, respectively, of fiber initials. Overexpressing GhCaM7 promotes early fiber elongation, whereas GhCaM7 suppression by RNAi delays fiber initiation and inhibits fiber elongation. Reactive oxygen species (ROS) play important roles in early fiber development. ROS induced by exogenous hydrogen peroxide (H2 O2 ) and Ca(2+) starvation promotes early fiber elongation. GhCaM7 overexpression fiber cells show increased ROS concentrations compared with the wild-type, while GhCaM7 RNAi fiber cells have reduced concentrations. Furthermore, we show that H2 O2 enhances Ca(2+) influx into the fiber and feedback-regulates the expression of GhCaM7. We conclude that GhCaM7, Ca(2+) and ROS are three important regulators involved in early fiber elongation. GhCaM7 might modulate ROS production and act as a molecular link between Ca(2+) and ROS signal pathways in early fiber development.
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Cálcio/metabolismo , Calmodulina/metabolismo , Genes de Plantas , Gossypium/metabolismo , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sementes/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Calmodulina/genética , Fibra de Algodão , Gossypium/genética , Gossypium/crescimento & desenvolvimento , Proteínas de Plantas/genética , Sementes/crescimento & desenvolvimento , Transdução de SinaisRESUMO
In this study, we examined whether common variants in the G protein-coupled receptor kinase 6 gene (GRK6) confers susceptibility to schizophrenia in Chinese. We genotyped two common variants in 697 schizophrenia patients and 563 healthy control subjects. No significant difference in either allele or genotype comparisons between the case and control groups was found. Our results imply that GRK6 may not play a role in the pathophysiology of schizophrenia among Han Chinese.
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Quinases de Receptores Acoplados a Proteína G/genética , Predisposição Genética para Doença , Esquizofrenia/genética , Adulto , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Variação Genética , Genótipo , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Esquizofrenia/fisiopatologia , Adulto JovemRESUMO
The phytohormone auxin exerts control over remarkable developmental processes in plants. It moves from cell to cell, resulting in the creation of both extracellular auxin and intracellular auxin, which are recognized by distinct auxin receptors. These two auxin signaling systems govern different auxin responses while working together to regulate plant development. In this review, we outline the latest research advancements in unraveling these auxin signaling pathways, encompassing auxin perception and signaling transductions. We emphasize the interaction between extracellular auxin and intracellular auxin, which contributes to the intricate role of auxin in plant development.
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Purpose: This study aimed to investigate the characteristics of various pulmonary lesions as revealed by 68Ga-FAPI PET/CT and to determine the utility of 68Ga-FAPI PET/CT in distinguishing the nature of these pulmonary lesions. Methods: A retrospective analysis was conducted on 99 patients with pulmonary lesions, who were categorized into three distinct groups: primary lung tumors (G1), metastatic lung tumors (G2), and benign lesions (G3). Each participant underwent a 68Ga-FAPI PET/CT scan. Among these groups, variables such as the Tumor/Background Ratio (TBR), Maximum Standardized Uptake Value (SUVmax), and the true positive rate of the lesions were compared. Furthermore, the FAPI uptake in nodular-like pulmonary lesions (d<3cm) and those with irregular borders was evaluated across the groups. A correlation analysis sought to understand the relationship between FAPI uptake in primary and pulmonary metastatic lesions. Results: The study's participants were composed of 52 males and 47 females, with an average age of 56.8 ± 13.2 years. A higher uptake and detection rate for pulmonary lesions were exhibited by Group G1 compared to the other groups (SUVmax [G1 vs. G2 vs. G3: 9.1 ± 4.1 vs. 6.1 ± 4.1 vs. 5.3 ± 5.8], P<0.05; TBR [G1 vs. G2 vs. G3: 6.2 ± 2.4 vs. 4.1 ± 2.2 vs. 3.2 ± 2.7], P<0.01; true positive rate 95.1% vs. 88% vs. 75.6%]. In nodular-like lung lesions smaller than 3 cm, G1 showed a significantly higher FAPI uptake compared to G2 and G3 (SUVmax [G1 vs. G2 vs. G3: 8.8 ± 4.3 vs. 5.2 ± 3.2 vs. 4.9 ± 6.1], P<0.01; TBR [G1 vs. G2 vs. G3: 5.7 ± 2.7 vs. 3.7 ± 2.1 vs. 3.3 ± 4.4], P<0.05). Both G1 and G2 demonstrated significantly elevated FAPI agent activity in irregular-bordered pulmonary lesions when compared to G3 (SUVmax [G1 vs. G2 vs. G3: 10.9 ± 3.3 vs. 8.5 ± 2.7 vs. 4.6 ± 2.7], P<0.01; TBR [G1 vs. G2 vs. G3: 7.2 ± 2.1 vs. 6.4 ± 1.3 vs. 3.2 ± 2.4], P<0.01). A positive correlation was identified between the level of 68Ga-FAPI uptake in primary lesions and the uptake in pulmonary metastatic lesions within G2 (r=0.856, P<0.05). Conclusion: 68Ga-FAPI PET/CT imaging proves to be of significant value in the evaluation of pulmonary lesions, offering distinctive insights into their nature.
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ABSTRACT: We present a case of pulmonary inflammatory pseudotumor with elevated 68 Ga-FAPI activity. Our case suggested that pulmonary inflammatory pseudotumor should be considered in the differential diagnosis of cancer-like solitary pulmonary nodules with increased 68 Ga-FAPI uptake.