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1.
Plant Cell ; 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37795677

RESUMO

Plant inflorescence architecture is determined by inflorescence meristem (IM) activity and controlled by genetic mechanisms associated with environmental factors. In Arabidopsis (Arabidopsis thaliana), TERMINAL FLOWER1 (TFL1) is expressed in the IM and is required to maintain indeterminate growth, whereas LEAFY (LFY) is expressed in the floral meristems (FMs) formed at the periphery of the IM and is required to activate determinate floral development. Here, we address how Arabidopsis indeterminate inflorescence growth is determined. We show that the 26S proteasome subunit REGULATORY PARTICLE AAA-ATPASE 2a (RPT2a) is required to maintain the indeterminate inflorescence architecture in Arabidopsis. rpt2a mutants display reduced TFL1 expression levels and ectopic LFY expression in the IM and develop a determinate zigzag-shaped inflorescence. We further found that RPT2a promotes DNA METHYLTRANSFERASE1 degradation, leading to DNA hypomethylation upstream of TFL1 and high TFL1 expression levels in the wild-type IM. Overall, our work reveals that proteolytic input into the epigenetic regulation of TFL1 expression directs inflorescence architecture in Arabidopsis, adding an additional layer to stem cell regulation.

4.
Nat Mater ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831130

RESUMO

The coexistence of correlated electron and hole crystals enables the realization of quantum excitonic states, capable of hosting counterflow superfluidity and topological orders with long-range quantum entanglement. Here we report evidence for imbalanced electron-hole crystals in a doped Mott insulator, namely, α-RuCl3, through gate-tunable non-invasive van der Waals doping from graphene. Real-space imaging via scanning tunnelling microscopy reveals two distinct charge orderings at the lower and upper Hubbard band energies, whose origin is attributed to the correlation-driven honeycomb hole crystal composed of hole-rich Ru sites and rotational-symmetry-breaking paired electron crystal composed of electron-rich Ru-Ru bonds, respectively. Moreover, a gate-induced transition of electron-hole crystals is directly visualized, further corroborating their nature as correlation-driven charge crystals. The realization and atom-resolved visualization of imbalanced electron-hole crystals in a doped Mott insulator opens new doors in the search for correlated bosonic states within strongly correlated materials.

5.
Plant Physiol ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743633

RESUMO

The cultivated apple (Malus domestica Borkh.) is a cross-pollinated perennial fruit tree of great economic importance. Previous versions of apple reference genomes were unphased, fragmented, and lacked comprehensive insights into the highly heterozygous genome, which impeded genetic studies and breeding programs in apple. In this study, we assembled a haplotype-resolved telomere-to-telomere reference genome for the diploid apple cultivar Golden Delicious. Subsequently, we constructed a pangenome based on twelve assemblies from wild and cultivated apples to investigate different types of resistance gene analogs (RGAs). Our results revealed the dynamics of the gene gain and loss events during apple domestication. Compared with cultivated species, more gene families in wild species were significantly enriched in oxidative phosphorylation, pentose metabolic process, responses to salt, and abscisic acid biosynthesis process. Interestingly, our analyses demonstrated a higher prevalence of RGAs in cultivated apples than their wild relatives, partially attributed to segmental and tandem duplication events in certain RGAs classes. Other types of structural variations, mainly deletions and insertions, have affected the presence and absence of TIR-NB-ARC-LRR (TNL), NB-ARC-LRR (NL), and CC-NB-ARC-LRR (CNL) genes. Additionally, hybridization/introgression from wild species has also contributed to the expansion of resistance genes in domesticated apples. Our haplotype-resolved T2T genome and pangenome provide important resources for genetic studies of apples, emphasizing the need to study the evolutionary mechanisms of resistance genes in apple breeding programs.

6.
Mol Cell ; 66(1): 141-153.e6, 2017 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-28388439

RESUMO

Mitochondria play an integral role in cell death, autophagy, immunity, and inflammation. We previously showed that Nur77, an orphan nuclear receptor, induces apoptosis by targeting mitochondria. Here, we report that celastrol, a potent anti-inflammatory pentacyclic triterpene, binds Nur77 to inhibit inflammation and induce autophagy in a Nur77-dependent manner. Celastrol promotes Nur77 translocation from the nucleus to mitochondria, where it interacts with tumor necrosis factor receptor-associated factor 2 (TRAF2), a scaffold protein and E3 ubiquitin ligase important for inflammatory signaling. The interaction is mediated by an LxxLL motif in TRAF2 and results not only in the inhibition of TRAF2 ubiquitination but also in Lys63-linked Nur77 ubiquitination. Under inflammatory conditions, ubiquitinated Nur77 resides at mitochondria, rendering them sensitive to autophagy, an event involving Nur77 interaction with p62/SQSTM1. Together, our results identify Nur77 as a critical intracellular target for celastrol and unravel a mechanism of Nur77-dependent clearance of inflamed mitochondria to alleviate inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Autofagia/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Fator 2 Associado a Receptor de TNF/metabolismo , Triterpenos/farmacologia , Ubiquitinação/efeitos dos fármacos , Transporte Ativo do Núcleo Celular , Animais , Anti-Inflamatórios/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Modelos Animais de Doenças , Feminino , Genótipo , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Ligantes , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/deficiência , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Triterpenos Pentacíclicos , Fenótipo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Interferência de RNA , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator 2 Associado a Receptor de TNF/genética , Transfecção , Triterpenos/metabolismo
7.
Proc Natl Acad Sci U S A ; 119(46): e2207201119, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36343244

RESUMO

The transcription variation, leading to various forms of transcripts and protein diversity, remains largely unexplored in triple-negative breast cancers (TNBCs). Here, we presented a comprehensive analysis of RNA splicing in breast cancer to illustrate the biological function and clinical implications of tumor-specific transcripts (TSTs) arising from these splicing junctions. Aberrant RNA splicing or TSTs were frequently harbored in TNBC and were correlated with a poor outcome. We discovered a tumor-specific splicing variant of macrophage receptor with collagenous structure-TST (MARCO-TST), which was distinguished from myeloid cell-specific wild-type MARCO. MARCO-TST expression was associated with poor outcomes in TNBC patients and could promote tumor progression in vitro and in vivo. Mechanically, MARCO-TST interacted with PLOD2 and enhanced the stability of HIF-1α, which resulted in the metabolic dysregulation of TNBC to form a hypoxic tumor microenvironment. MARCO-TST was initiated from a de novo alternative transcription initiation site that was activated by a superenhancer. Tumors with MARCO-TST expression conferred greater sensitivity to bromodomain and extraterminal protein inhibitors. This treatment strategy was further validated in patient-derived organoids. In conclusion, our results revealed the transcription variation landscape of TNBC, highlighting MARCO-TST as a crucial oncogenic transcript and therapeutic target.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/metabolismo , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Carcinogênese/genética , Splicing de RNA , Proliferação de Células , Microambiente Tumoral
8.
J Cell Physiol ; 239(1): 124-134, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37942832

RESUMO

Studies regarding age-related erectile dysfunction (ED) based on naturally aging models are limited by their high costs, especially for the acquisition of primary cells from the corpus cavernosum. Herein, d-galactose ( d-gal) was employed to accelerate cell senescence, and the underlying mechanism was explored. As predominant functional cells involved in the erectile response, corpus cavernosum smooth muscle cells (CCSMCs) were isolated from 2-month-old rats. Following this, d-gal was introduced to induce cell senescence, which was verified via ß-galactosidase staining. The effects of d-gal on CCSMCs were evaluated by terminal deoxynucleoitidyl transferase dUTP nick-end labeling (TUNEL), immunofluorescence staining, flow cytometry, western blot, and quantitative real-time polymerase chain reaction (qRT-PCR). Furthermore, RNA interference (RNAi) was carried out for rescue experiments. Subsequently, the influence of senescence on the corpus cavernosum was determined via scanning electron microscopy, qRT-PCR, immunohistochemistry, TUNEL, and Masson stainings. The results revealed that the accelerated senescence of CCSMCs was promoted by d-gal. Simultaneously, smooth muscle alpha-actin (alpha-SMA) expression was inhibited, while that of osteopontin (OPN) and Krüppel-like factor 4 (KLF4), as well as fibrotic and apoptotic levels, were elevated. After knocking down KLF4 expression in d-gal-induced CCSMCs by RNAi, the expression level of cellular alpha-SMA increased. Contrastingly, the OPN expression, apoptotic and fibrotic levels declined. In addition, cellular senescence acquired partial remission. Accordingly, in the aged corpus cavernosum, the fibrotic and apoptotic rates were increased, followed by downregulation in the expression of alpha-SMA and the concurrent upregulation in the expression of OPN and KLF4. Overall, our results signaled that d-gal-induced accelerated senescence of CCSMCs could trigger fibrosis, apoptosis and phenotypic switch to the synthetic state, potentially attributed to the upregulation of KLF4 expression, which may be a multipotential therapeutic target of age-related ED.


Assuntos
Disfunção Erétil , Galactose , Miócitos de Músculo Liso , Animais , Masculino , Ratos , Disfunção Erétil/metabolismo , Disfunção Erétil/terapia , Galactose/farmacologia , Galactose/metabolismo , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Pênis , Fenótipo , Ratos Sprague-Dawley , Actinas
9.
J Am Chem Soc ; 146(1): 833-848, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38113458

RESUMO

The high-performance Y6-based nonfullerene acceptors (NFAs) feature a C-shaped A-DA'D-A-type molecular architecture with a central electron-deficient thiadiazole (Tz) A' unit. In this work, we designed and synthesized a new A-D-A-type NFA, termed CB16, having a C-shaped ortho-benzodipyrrole-based skeleton of Y6 but with the Tz unit eliminated. When processed with nonhalogenated xylene without using any additives, the binary PM6:CB16 devices display a remarkable power conversion efficiency (PCE) of 18.32% with a high open-circuit voltage (Voc) of 0.92 V, surpassing the performance of the corresponding Y6-based devices. In contrast, similarly synthesized SB16, featuring an S-shaped para-benzodipyrrole-based skeleton, yields a low PCE of 0.15% due to the strong side-chain aggregation of SB16. The C-shaped A-DNBND-A skeleton in CB16 and the Y6-series NFAs constitutes the essential structural foundation for achieving exceptional device performance. The central Tz moiety or other A' units can be employed to finely adjust intermolecular interactions. The single-crystal X-ray structure reveals that ortho-benzodipyrrole-embedded A-DNBND-A plays an important role in the formation of a 3D elliptical network packing for efficient charge transport. Solution structures of the PM6:NFAs detected by small- and wide-angle X-ray scattering (SWAXS) indicate that removing the Tz unit in the C-shaped skeleton could reduce the self-packing of CB16, thereby enhancing the complexing and networking with PM6 in the spin-coating solution and the subsequent device film. Elucidating the structure-property-performance relationships of A-DA'D-A-type NFAs in this work paves the way for the future development of structurally simplified A-D-A-type NFAs.

10.
Br J Cancer ; 130(8): 1286-1294, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38388856

RESUMO

BACKGROUND: We characterized age at diagnosis and estimated sex differences for lung cancer and its histological subtypes among individuals who never smoke. METHODS: We analyzed the distribution of age at lung cancer diagnosis in 33,793 individuals across 8 cohort studies and two national registries from East Asia, the United States (US) and the United Kingdom (UK). Student's t-tests were used to assess the study population differences (Δ years) in age at diagnosis comparing females and males who never smoke across subgroups defined by race/ethnicity, geographic location, and histological subtypes. RESULTS: We found that among Chinese individuals diagnosed with lung cancer who never smoke, females were diagnosed with lung cancer younger than males in the Taiwan Cancer Registry (n = 29,832) (Δ years = -2.2 (95% confidence interval (CI):-2.5, -1.9), in Shanghai (n = 1049) (Δ years = -1.6 (95% CI:-2.9, -0.3), and in Sutter Health and Kaiser Permanente Hawai'i in the US (n = 82) (Δ years = -11.3 (95% CI: -17.7, -4.9). While there was a suggestion of similar patterns in African American and non-Hispanic White individuals. the estimated differences were not consistent across studies and were not statistically significant. CONCLUSIONS: We found evidence of sex differences for age at lung cancer diagnosis among individuals who never smoke.


Assuntos
Etnicidade , Neoplasias Pulmonares , Humanos , Masculino , Feminino , Estados Unidos/epidemiologia , Fumaça , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/patologia , China , Brancos
11.
Biochem Biophys Res Commun ; 702: 149633, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38341921

RESUMO

Ribosomal protein 25 (RPS25) has been related to male fertility diseases in humans. However, the role of RPS25 in spermatogenesis has yet to be well understood. RpS25 is evolutionarily highly conserved from flies to humans through sequence alignment and phylogenetic tree construction. In this study, we found that RpS25 plays a critical role in Drosophila spermatogenesis and its knockdown leads to male sterility. Examination of each stage of spermatogenesis from RpS25-knockdown flies showed that RpS25 was not required for initial germline cell divisions, but was required for spermatid elongation and individualization. In RpS25-knockdown testes, the average length of cyst elongation was shortened, the spermatid nuclei bundling was disrupted, and the assembly of individualization complex from actin cones failed, resulting in the failure of mature sperm production. Our data revealed an essential role of RpS25 during Drosophila spermatogenesis through regulating spermatid elongation and individualization.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Humanos , Masculino , Drosophila/genética , Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Filogenia , Sêmen/metabolismo , Espermátides/metabolismo , Espermatogênese/genética , Espermatozoides/metabolismo , Testículo/metabolismo
12.
Small ; : e2400458, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607289

RESUMO

1D nanowire networks, sharing similarities of structure, information transfer, and computation with biological neural networks, have emerged as a promising platform for neuromorphic systems. Based on brain-like structures of 1D nanowire networks, neuromorphic synaptic devices can overcome the von Neumann bottleneck, achieving intelligent high-efficient sensing and computing function with high information processing rates and low power consumption. Here, high-temperature neuromorphic synaptic devices based on SiC@NiO core-shell nanowire networks optoelectronic memristors (NNOMs) are developed. Experimental results demonstrate that NNOMs attain synaptic short/long-term plasticity and modulation plasticity under both electrical and optical stimulation, and exhibit advanced functions such as short/long-term memory and "learning-forgetting-relearning" under optical stimulation at both room temperature and 200 °C. Based on the advanced functions under light stimulus, the constructed 5 × 3 optoelectronic synaptic array devices exhibit a stable visual memory function up to 200 °C, which can be utilized to develop artificial visual systems. Additionally, when exposed to multiple electronic or optical stimuli, the NNOMs effectively replicate the principles of Pavlovian classical conditioning, achieving visual heterologous synaptic functionality and refining neural networks. Overall, with abundant synaptic characteristics and high-temperature thermal stability, these neuromorphic synaptic devices offer a promising route for advancing neuromorphic computing and visual systems.

13.
J Transl Med ; 22(1): 571, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38879493

RESUMO

BACKGROUND: No reliable clinical tools exist to predict acute kidney injury (AKI) progression. We aim to explore a scoring system for predicting the composite outcome of progression to severe AKI or death within seven days among early AKI patients after cardiac surgery. METHODS: In this study, we used two independent cohorts, and patients who experienced mild/moderate AKI within 48 h after cardiac surgery were enrolled. Eventually, 3188 patients from the MIMIC-IV database were used as the derivation cohort, while 499 patients from the Zhongshan cohort were used as external validation. The primary outcome was defined by the composite outcome of progression to severe AKI or death within seven days after enrollment. The variables identified by LASSO regression analysis were entered into logistic regression models and were used to construct the risk score. RESULTS: The composite outcome accounted for 3.7% (n = 119) and 7.6% (n = 38) of the derivation and validation cohorts, respectively. Six predictors were assembled into a risk score (AKI-Pro score), including female, baseline eGFR, aortic surgery, modified furosemide responsiveness index (mFRI), SOFA, and AKI stage. And we stratified the risk score into four groups: low, moderate, high, and very high risk. The risk score displayed satisfied predictive discrimination and calibration in the derivation and validation cohort. The AKI-Pro score discriminated the composite outcome better than CRATE score, Cleveland score, AKICS score, Simplified renal index, and SRI risk score (all P < 0.05). CONCLUSIONS: The AKI-Pro score is a new clinical tool that could assist clinicians to identify early AKI patients at high risk for AKI progression or death.


Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Progressão da Doença , Humanos , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/diagnóstico , Feminino , Masculino , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Estudos de Coortes , Índice de Gravidade de Doença , Curva ROC , Medição de Risco , Prognóstico
14.
Genet Med ; : 101201, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38953292

RESUMO

PURPOSE: This study compared Lynch syndrome universal tumor screening (UTS) across multiple health systems (some of which had two or more distinct UTS programs) to understand multi-level factors that may impact the successful implementation of complex programs. METHODS: Data from 66 stakeholder interviews were used to conduct multi-value coincidence analysis (mv-CNA) and identify key factors that consistently make a difference in whether UTS programs were implemented and optimized at the system level. RESULTS: The selected CNA model revealed combinations of conditions that distinguish 4 optimized UTS programs, 10 non-optimized programs, and 4 systems with no program. Fully optimized UTS programs had both a maintenance champion and a positive inner setting. Two independent paths were unique to non-optimized programs: 1) positive attitudes and a mixed inner setting, or 2) limited planning & engaging among stakeholders. Negative views about UTS evidence or lack of knowledge about UTS led to a lack of planning and engaging, which subsequently prevented program implementation. CONCLUSION: The model improved our understanding of program implementation in health care systems and informed the creation of a toolkit to guide UTS implementation, optimization, and changes. Our findings and toolkit may serve as a use case to increase the successful implementation of other complex precision health programs.

15.
New Phytol ; 242(3): 1098-1112, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38515249

RESUMO

The potential for totipotency exists in all plant cells; however, the underlying mechanisms remain largely unknown. Earlier findings have revealed that the overexpression of LEAFY COTYLEDON 2 (LEC2) can directly trigger the formation of somatic embryos on the cotyledons of Arabidopsis. Furthermore, cotyledon cells that overexpress LEC2 accumulate significant lipid reserves typically found in seeds. The precise mechanisms and functions governing lipid accumulation in this process remain unexplored. In this study, we demonstrate that WRINKLED1 (WRI1), the key regulator of lipid biosynthesis, is essential for somatic embryo formation, suggesting that WRI1-mediated lipid biosynthesis plays a crucial role in the transition from vegetative to embryonic development. Our findings indicate a direct interaction between WRI1 and LEC2, which enhances the enrichment of LEC2 at downstream target genes and stimulates their induction. Besides, our data suggest that WRI1 forms a complex with LEC1, LEC2, and FUSCA3 (FUS3) to facilitate the accumulation of auxin and lipid for the somatic embryo induction, through strengthening the activation of YUCCA4 (YUC4) and OLEOSIN3 (OLE3) genes. Our results uncover a regulatory module controlled by WRI1, crucial for somatic embryogenesis. These findings provide valuable insights into our understanding of plant cell totipotency.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Lipídeos , Sementes/genética , Fatores de Transcrição/metabolismo
16.
J Med Virol ; 96(1): e29348, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38180275

RESUMO

Ground glass hepatocytes (GGHs) have been associated with hepatocellular carcinoma (HCC) recurrence and poor prognosis. We previously demonstrated that pre-S expression in some GGHs is resistant to current hepatitis B virus (HBV) antiviral therapies. This study aimed to investigate whether integrated HBV DNA (iDNA) is the primary HBV DNA species responsible for sustained pre-S expression in GGH after effective antiviral therapy. We characterized 10 sets of micro-dissected, formalin-fixed-paraffin-embedded, and frozen GGH, HCC, and adjacent hepatitis B surface antigen-negative stained tissues for iDNA, pre-S deletions, and the quantity of covalently closed circular DNA. Eight patients had detectable pre-S deletions, and nine had detectable iDNA. Interestingly, eight patients had integrations within the TERT and CCNE1 genes, which are known recurrent integration sites associated with HCC. Furthermore, we observed a recurrent integration in the ABCC13 gene. Additionally, we identified variations in the type and quantity of pre-S deletions within individual sets of tissues by junction-specific PacBio long-read sequencing. The data from long-read sequencing indicate that some pre-S deletions were acquired following the integration events. Our findings demonstrate that iDNA exists in GGH and can be responsible for sustained pre-S expression in GGH after effective antiviral therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Vírus da Hepatite B/genética , DNA Viral/genética , Neoplasias Hepáticas/genética , Hepatócitos , Mutação , Antivirais/uso terapêutico
17.
Plant Cell ; 33(6): 1907-1926, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-33730150

RESUMO

Seed size is a major factor determining crop yields that is controlled through the coordinated development of maternal and zygotic tissues. Here, we identified Arabidopsis MATERNAL EFFECT EMBRYO ARREST45 (MEE45) as a B3 transcription factor that controls cell proliferation and maternally regulates seed size through its transcriptional activation of AINTEGUMENTA (ANT) and its downstream control of auxin biosynthesis in the ovule integument. After characterizing reduced seed and organ size phenotypes in mee45 mutants and finding that overexpression of MEE45 causes oversized seeds, we discovered that the MEE45 protein can bind to the promoter region of the ANT locus and positively regulate its transcription. ANT in-turn activates the expression of auxin biosynthetic genes (e.g. YUCCA4) in the ovule integument. Our results thus illustrate mechanisms underlying maternal tissue-mediated regulation of seed size and suggest that MEE45 and its downstream components can be harnessed to develop higher-yielding crop varieties.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Sementes/crescimento & desenvolvimento , Fatores de Transcrição/genética , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proliferação de Células/genética , Regulação da Expressão Gênica de Plantas , Herança Materna/genética , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Tamanho do Órgão , Óvulo Vegetal/citologia , Óvulo Vegetal/genética , Células Vegetais , Plantas Geneticamente Modificadas , Sementes/genética , Fatores de Transcrição/metabolismo
18.
Int J Neuropsychopharmacol ; 27(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38135278

RESUMO

BACKGROUND: Melanin-concentrating hormone (MCH) is a hypothalamic neuropeptide that projects throughout the central nervous system, including the noradrenergic locus coeruleus (LC). Our previous study suggested that MCH/MCH receptor 1 (MCHR1) in the LC may be involved in the regulation of depression. The present study investigated whether the role of MCH/MCHR1 in the LC in depression-like behaviors is associated with the regulation of norepinephrine. METHOD: Chronic unpredictable stress (CUS) and an acute intra-LC microinjection of MCH induced depression-like behaviors in rats. The MCHR1 antagonist SNAP-94847 was also microinjected in the LC in rats that were suffering CUS or treated with MCH. The sucrose preference, forced swim, and locomotor tests were used for behavioral evaluation. Immunofluorescence staining, enzyme-linked immunosorbent assay, western blot, and high-performance liquid chromatography with electrochemical detection were used to explore the mechanism of MCH/MCHR1 in the regulation of depression-like behaviors. RESULTS: CUS induced an abnormal elevation of MCH levels and downregulated MCHR1 in the LC, which was highly correlated with the formation of depression-like behaviors. SNAP-94847 exerted antidepressant effects in CUS-exposed rats by normalizing tyrosine hydroxylase, dopamine ß hydroxylase, and norepinephrine in the LC. An acute microinjection of MCH induced depression-like behaviors through its action on MCHR1. MCHR1 antagonism in the LC significantly reversed the MCH-induced downregulation of norepinephrine production by normalizing MCHR1-medicated cAMP-PKA signaling. CONCLUSIONS: Our study confirmed that the MCH/MCHR1 system in the LC may be involved in depression-like behaviors by downregulating norepinephrine production. These results improve our understanding of the pathogenesis of depression that is related to the MCH/MCHR1 system in the LC.


Assuntos
Hormônios Hipotalâmicos , Locus Cerúleo , Ratos , Animais , Depressão/induzido quimicamente , Depressão/tratamento farmacológico , Norepinefrina , Hormônios Hipotalâmicos/metabolismo , Hormônios Hipofisários/farmacologia , Melaninas/farmacologia
19.
Phys Rev Lett ; 132(24): 246902, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949373

RESUMO

We show that excitonic resonances and interexciton transitions can enhance the probability of spontaneous parametric down-conversion, a second-order optical response that generates entangled photon pairs. We benchmark our ab initio many-body calculations using experimental polar plots of second harmonic generation in NbOI_{2}, clearly demonstrating the relevance of excitons in the nonlinear response. A strong double-exciton resonance in 2D NbOCl_{2} leads to giant enhancement in the second order susceptibility. Our work paves the way for the realization of efficient ultrathin quantum light sources.

20.
Exp Eye Res ; 239: 109784, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199261

RESUMO

Transient receptor potential vanilloid (TRPV) channels are members of the TRP channel superfamily, which are ion channels that sense mechanical and osmotic stimuli and participate in Ca2+ signalling across the cell membrane. TRPV channels play important roles in maintaining the normal functions of an organism, and defects or abnormalities in TRPV channel function cause a range of diseases, including cardiovascular, neurological and urological disorders. Glaucoma is a group of chronic progressive optic nerve diseases with pathological changes that can occur in the tissues of the anterior and posterior segments of the eye, including the ciliary body, trabecular meshwork, Schlemm's canal, and retina. TRPV channels are expressed in these tissues and play various roles in glaucoma. In this article, we review various aspects of the pathogenesis of glaucoma, the structure and function of TRPV channels, the relationship between TRPV channels and systemic diseases, and the relationship between TRPV channels and ocular diseases, especially glaucoma, and we suggest future research directions. This information will help to further our understanding of TRPV channels and provide new ideas and targets for the treatment of glaucoma and optic nerve damage.


Assuntos
Glaucoma , Traumatismos do Nervo Óptico , Humanos , Esclera/patologia , Retina/patologia , Malha Trabecular/metabolismo , Traumatismos do Nervo Óptico/metabolismo , Nervo Óptico/patologia
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