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1.
Plant Cell ; 36(5): 1892-1912, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38262703

RESUMO

In cereal grains, starch is synthesized by the concerted actions of multiple enzymes on the surface of starch granules within the amyloplast. However, little is known about how starch-synthesizing enzymes access starch granules, especially for amylopectin biosynthesis. Here, we show that the rice (Oryza sativa) floury endosperm9 (flo9) mutant is defective in amylopectin biosynthesis, leading to grains exhibiting a floury endosperm with a hollow core. Molecular cloning revealed that FLO9 encodes a plant-specific protein homologous to Arabidopsis (Arabidopsis thaliana) LIKE EARLY STARVATION1 (LESV). Unlike Arabidopsis LESV, which is involved in starch metabolism in leaves, OsLESV is required for starch granule initiation in the endosperm. OsLESV can directly bind to starch by its C-terminal tryptophan (Trp)-rich region. Cellular and biochemical evidence suggests that OsLESV interacts with the starch-binding protein FLO6, and loss-of-function mutations of either gene impair ISOAMYLASE1 (ISA1) targeting to starch granules. Genetically, OsLESV acts synergistically with FLO6 to regulate starch biosynthesis and endosperm development. Together, our results identify OsLESV-FLO6 as a non-enzymatic molecular module responsible for ISA1 localization on starch granules, and present a target gene for use in biotechnology to control starch content and composition in rice endosperm.


Assuntos
Endosperma , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Amido , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Endosperma/metabolismo , Endosperma/genética , Amido/metabolismo , Amido/biossíntese , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Amilopectina/metabolismo , Mutação , Plantas Geneticamente Modificadas
2.
Proc Natl Acad Sci U S A ; 121(10): e2309957121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38422022

RESUMO

Hypoxia signaling influences tumor development through both cell-intrinsic and -extrinsic pathways. Inhibiting hypoxia-inducible factor (HIF) function has recently been approved as a cancer treatment strategy. Hence, it is important to understand how regulators of HIF may affect tumor growth under physiological conditions. Here we report that in aging mice factor-inhibiting HIF (FIH), one of the most studied negative regulators of HIF, is a haploinsufficient suppressor of spontaneous B cell lymphomas, particular pulmonary B cell lymphomas. FIH deficiency alters immune composition in aged mice and creates a tumor-supportive immune environment demonstrated in syngeneic mouse tumor models. Mechanistically, FIH-defective myeloid cells acquire tumor-supportive properties in response to signals secreted by cancer cells or produced in the tumor microenvironment with enhanced arginase expression and cytokine-directed migration. Together, these data demonstrate that under physiological conditions, FIH plays a key role in maintaining immune homeostasis and can suppress tumorigenesis through a cell-extrinsic pathway.


Assuntos
Linfoma de Células B , Proteínas Repressoras , Animais , Camundongos , Hipóxia/metabolismo , Oxigenases de Função Mista/metabolismo , Proteínas Repressoras/metabolismo , Microambiente Tumoral
3.
Plant Cell ; 35(8): 2871-2886, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37195873

RESUMO

Plants have evolved sophisticated mechanisms to coordinate their growth and stress responses via integrating various phytohormone signaling pathways. However, the precise molecular mechanisms orchestrating integration of the phytohormone signaling pathways remain largely obscure. In this study, we found that the rice (Oryza sativa) short internodes1 (shi1) mutant exhibits typical auxin-deficient root development and gravitropic response, brassinosteroid (BR)-deficient plant architecture and grain size as well as enhanced abscisic acid (ABA)-mediated drought tolerance. Additionally, we found that the shi1 mutant is also hyposensitive to auxin and BR treatment but hypersensitive to ABA. Further, we showed that OsSHI1 promotes the biosynthesis of auxin and BR by activating the expression of OsYUCCAs and D11, meanwhile dampens ABA signaling by inducing the expression of OsNAC2, which encodes a repressor of ABA signaling. Furthermore, we demonstrated that 3 classes of transcription factors, AUXIN RESPONSE FACTOR 19 (OsARF19), LEAF AND TILLER ANGLE INCREASED CONTROLLER (LIC), and OsZIP26 and OsZIP86, directly bind to the promoter of OsSHI1 and regulate its expression in response to auxin, BR, and ABA, respectively. Collectively, our results unravel an OsSHI1-centered transcriptional regulatory hub that orchestrates the integration and self-feedback regulation of multiple phytohormone signaling pathways to coordinate plant growth and stress adaptation.


Assuntos
Oryza , Reguladores de Crescimento de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Abscísico/metabolismo , Ácidos Indolacéticos/metabolismo , Brassinosteroides/metabolismo , Hormônios , Crescimento e Desenvolvimento , Regulação da Expressão Gênica de Plantas
4.
BMC Genomics ; 25(1): 132, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302871

RESUMO

BACKGROUND: The U-box gene family encodes E3 ubiquitin ligases involved in plant hormone signaling pathways and abiotic stress responses. However, there has yet to be a comprehensive analysis of the U-box gene family in maize (Zea mays L.) and its responses to abiotic stress. RESULTS: In this study, 85 U-box family proteins were identified in maize and were classified into four subfamilies based on phylogenetic analysis. In addition to the conserved U-box domain, we identified additional functional domains, including Pkinase, ARM, KAP and Tyr domains, by analyzing the conserved motifs and gene structures. Chromosomal localization and collinearity analysis revealed that gene duplications may have contributed to the expansion and evolution of the U-box gene family. GO annotation and KEGG pathway enrichment analysis identified a total of 105 GO terms and 21 KEGG pathways that were notably enriched, including ubiquitin-protein transferase activity, ubiquitin conjugating enzyme activity and ubiquitin-mediated proteolysis pathway. Tissue expression analysis showed that some ZmPUB genes were specifically expressed in certain tissues and that this could be due to their functions. In addition, RNA-seq data for maize seedlings under salt stress revealed 16 stress-inducible plant U-box genes, of which 10 genes were upregulated and 6 genes were downregulated. The qRT-PCR results for genes responding to abiotic stress were consistent with the transcriptome analysis. Among them, ZmPUB13, ZmPUB18, ZmPUB19 and ZmPUB68 were upregulated under all three abiotic stress conditions. Subcellular localization analysis showed that ZmPUB19 and ZmPUB59 were located in the nucleus. CONCLUSIONS: Overall, our study provides a comprehensive analysis of the U-box gene family in maize and its responses to abiotic stress, suggesting that U-box genes play an important role in the stress response and providing insights into the regulatory mechanisms underlying the response to abiotic stress in maize.


Assuntos
Ubiquitina-Proteína Ligases , Zea mays , Zea mays/metabolismo , Filogenia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Perfilação da Expressão Gênica , Estresse Fisiológico/genética , Ubiquitinas/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Família Multigênica
5.
Br J Cancer ; 130(11): 1841-1854, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38553589

RESUMO

BACKGROUND: Despite the extensive study of MYCN-amplified neuroblastomas, there is a significant unmet clinical need in MYCN non-amplified cases. In particular, the extent of heterogeneity within the MYCN non-amplified population is unknown. METHODS: A total of 1566 samples from 16 datasets were identified in Gene Expression Omnibus (GEO) and ArrayExpress. Characterisation of the subtypes was analysed by ConsensusClusterPlus. Independent predictors for subgrouping were constructed from the single sample predictor based on the multiclassPairs package. Findings were verified using immunohistochemistry and CIBERSORTx analysis. RESULTS: We demonstrate that MYCN non-amplified neuroblastomas are heterogeneous and can be classified into 3 subgroups based on their transcriptional signatures. Within these groups, subgroup_2 has the worst prognosis and this group shows a 'MYCN' signature that is potentially induced by the overexpression of Aurora Kinase A (AURKA); whilst subgroup_3 is characterised by an 'inflamed' gene signature. The clinical implications of this subtype classification are significant, as each subtype demonstrates a unique prognosis and vulnerability to investigational therapies. A total of 420 genes were identified as independent subgroup predictors with average balanced accuracy of 0.93 and 0.84 for train and test datasets, respectively. CONCLUSION: We propose that transcriptional subtyping may enhance precision prognosis and therapy stratification for patients with MYCN non-amplified neuroblastomas.


Assuntos
Proteína Proto-Oncogênica N-Myc , Neuroblastoma , Humanos , Neuroblastoma/genética , Neuroblastoma/classificação , Neuroblastoma/patologia , Neuroblastoma/mortalidade , Proteína Proto-Oncogênica N-Myc/genética , Prognóstico , Aurora Quinase A/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , Amplificação de Genes
6.
New Phytol ; 242(6): 2635-2651, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38634187

RESUMO

Endosperm is the main storage organ in cereal grain and determines grain yield and quality. The molecular mechanisms of heat shock proteins in regulating starch biosynthesis and endosperm development remain obscure. Here, we report a rice floury endosperm mutant flo24 that develops abnormal starch grains in the central starchy endosperm cells. Map-based cloning and complementation test showed that FLO24 encodes a heat shock protein HSP101, which is localized in plastids. The mutated protein FLO24T296I dramatically lost its ability to hydrolyze ATP and to rescue the thermotolerance defects of the yeast hsp104 mutant. The flo24 mutant develops more severe floury endosperm when grown under high-temperature conditions than normal conditions. And the FLO24 protein was dramatically induced at high temperature. FLO24 physically interacts with several key enzymes required for starch biosynthesis, including AGPL1, AGPL3 and PHO1. Combined biochemical and genetic evidence suggests that FLO24 acts cooperatively with HSP70cp-2 to regulate starch biosynthesis and endosperm development in rice. Our results reveal that FLO24 acts as an important regulator of endosperm development, which might function in maintaining the activities of enzymes involved in starch biosynthesis in rice.


Assuntos
Endosperma , Regulação da Expressão Gênica de Plantas , Mutação , Oryza , Proteínas de Plantas , Amido , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Endosperma/metabolismo , Endosperma/crescimento & desenvolvimento , Amido/metabolismo , Amido/biossíntese , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Mutação/genética , Ligação Proteica , Plastídeos/metabolismo , Teste de Complementação Genética , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/biossíntese , Termotolerância , Fatores de Transcrição
7.
Eur Radiol ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38724768

RESUMO

OBJECTIVES: Developing a deep learning radiomics model from longitudinal breast ultrasound and sonographer's axillary ultrasound diagnosis for predicting axillary lymph node (ALN) response to neoadjuvant chemotherapy (NAC) in breast cancer. METHODS: Breast cancer patients undergoing NAC followed by surgery were recruited from three centers between November 2016 and December 2022. We collected ultrasound images for extracting tumor-derived radiomics and deep learning features, selecting quantitative features through various methods. Two machine learning models based on random forest were developed using pre-NAC and post-NAC features. A support vector machine integrated these data into a fusion model, evaluated via the area under the curve (AUC), decision curve analysis, and calibration curves. We compared the fusion model's performance against sonographer's diagnosis from pre-NAC and post-NAC axillary ultrasonography, referencing histological outcomes from sentinel lymph node biopsy or axillary lymph node dissection. RESULTS: In the validation cohort, the fusion model outperformed both pre-NAC (AUC: 0.899 vs. 0.786, p < 0.001) and post-NAC models (AUC: 0.899 vs. 0.853, p = 0.014), as well as the sonographer's diagnosis of ALN status on pre-NAC and post-NAC axillary ultrasonography (AUC: 0.899 vs. 0.719, p < 0.001). Decision curve analysis revealed patient benefits from the fusion model across threshold probabilities from 0.02 to 0.98. The model also enhanced sonographer's diagnostic ability, increasing accuracy from 71.9% to 79.2%. CONCLUSION: The deep learning radiomics model accurately predicted the ALN response to NAC in breast cancer. Furthermore, the model will assist sonographers to improve their diagnostic ability on ALN status before surgery. CLINICAL RELEVANCE STATEMENT: Our AI model based on pre- and post-neoadjuvant chemotherapy ultrasound can accurately predict axillary lymph node metastasis and assist sonographer's axillary diagnosis. KEY POINTS: Axillary lymph node metastasis status affects the choice of surgical treatment, and currently relies on subjective ultrasound. Our AI model outperformed sonographer's visual diagnosis on axillary ultrasound. Our deep learning radiomics model can improve sonographers' diagnosis and might assist in surgical decision-making.

8.
Orthod Craniofac Res ; 27(1): 174-184, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37985447

RESUMO

OBJECTIVE: To investigate the salivary bacterial communities during the first 6-month orthodontic treatment with Clear Aligners (CA) and Fixed Appliances (FA), and its correlation with clinical periodontal parameters. MATERIALS AND METHODS: Saliva and periodontal parameters were sampled from individuals wearing CA or FA before treatment (T0), and after 3- (T3) and 6-month (T6) treatments. Salivary bacterial communities characterized based on the 16S rRNA V3-V4 region were compared between FA and CA and correlated with clinical periodontal parameters. RESULTS: Probing Depth (PD) significantly increased at T6 in the FA group versus T0, whereas it remained stable in the CA group. The Shannon and Pielou indices were significantly higher in the FA group and significantly positively correlated with periodontal inflammation parameters. ß-diversity analysis revealed distinct communities between the FA group and CA group at T6. The relative abundances of 3 genera and 15 species were significantly higher in the FA group. Among the above appliance-type related taxa, bacterial genera Selenomonas, Stomatobaculum, Olsenella and Faecalicoccus and bacterial species Selenomonas_sputigena, Dialister_invisus, Olsenella_profus, Prevotella_buccae, Cryptobacterium_curtum and Clostridium_spiroforme were significantly positively associated with periodontal parameters. CONCLUSIONS: Orthodontic treatments trigger appliance-related salivary bacterial communities, highlighting the importance of developing appliance-orientated periodontal strategies during orthodontic treatments. Salivary bacterial communities harboured by patients wearing FA possess higher bacterial parameters which were associated with increasing PD, PI and Gingival Index.


Assuntos
Microbiota , Aparelhos Ortodônticos , Humanos , RNA Ribossômico 16S/genética , Aparelhos Ortodônticos Fixos , Saliva/microbiologia
9.
Ecotoxicol Environ Saf ; 270: 115889, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38150751

RESUMO

Silica nanoparticles (SiNPs) have been widely used in electronics, chemistry, and biomedicine. Human exposure to SiNPs and possible health effects have attracted much attention. The potential cardiovascular toxicity of SiNPs and their related mechanisms are still unclear. Therefore, in this study, we investigated the toxic effects of SiNPs on human umbilical vein endothelial cells (HUVECs). We found that SiNPs could induce HUVECs ferroptosis. The results showed that the level of intracellular divalent iron and lipid peroxidation increased, and mitochondrial cristae decreased. In addition, the pretreatment of the iron chelator deferoxamine mesylate (DFO) could alleviate the ferroptosis of cells. Interestingly, pretreatment of 3-methyladenine (3-MA), an autophagy/PI3K inhibitor could partially inhibit autophagy and reduce ferroptosis, which indicated that autophagy played an important role in cell ferroptosis. Additionally, after knocking down nuclear receptor coactivator 4 (NCOA4), Ferritin Heavy Chain 1 (FTH1) expression was up-regulated, and the levels of divalent iron and lipid peroxidation decreased, which suggested that NCOA4 mediated the ferroptosis of HUVECs induced by SiNPs. In conclusion, this study shows that SiNPs can induce cardiovascular toxicity in which there is ferroptosis. NCOA4-mediated ferritinophagy and resultant ferroptosis by SiNPs may play an important role. This study provides a new theoretical strategy for the treatment and prevention of cardiovascular diseases in the future.


Assuntos
Ferroptose , Nanopartículas , Humanos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Dióxido de Silício/toxicidade , Fosfatidilinositol 3-Quinases/metabolismo , Ferro/metabolismo , Fatores de Transcrição/metabolismo , Nanopartículas/toxicidade , Autofagia , Coativadores de Receptor Nuclear/genética , Coativadores de Receptor Nuclear/metabolismo
10.
Int J Mol Sci ; 25(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38256188

RESUMO

Nucleotidyl transferases (NTPs) are common transferases in eukaryotes and play a crucial role in nucleotide modifications at the 3' end of RNA. In plants, NTPs can regulate RNA stability by influencing 3' end modifications, which in turn affect plant growth, development, stress responses, and disease resistance. Although the functions of NTP family members have been extensively studied in Arabidopsis, rice, and maize, there is limited knowledge about NTP genes in soybeans. In this study, we identified 16 members of the NTP family in soybeans, including two subfamilies (G1 and G2) with distinct secondary structures, conserved motifs, and domain distributions at the protein level. Evolutionary analysis of genes in the NTP family across multiple species and gene collinearity analysis revealed a relatively conserved evolutionary pattern. Analysis of the tertiary structure of the proteins showed that NTPs have three conserved aspartic acids that bind together to form a possible active site. Tissue-specific expression analysis indicated that some NTP genes exhibit tissue-specific expression, likely due to their specific functions. Stress expression analysis showed significant differences in the expression levels of NTP genes under high salt, drought, and cold stress. Additionally, RNA-seq analysis of soybean plants subjected to salt and drought stress further confirmed the association of soybean NTP genes with abiotic stress responses. Subcellular localization experiments revealed that GmNTP2 and GmNTP14, which likely have similar functions to HESO1 and URT1, are located in the nucleus. These research findings provide a foundation for further investigations into the functions of NTP family genes in soybeans.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Nucleotidiltransferases , Glycine max/genética , Resposta ao Choque Frio , Nucleotídeos , RNA Nucleotidiltransferases
11.
J Cell Mol Med ; 27(12): 1637-1652, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37226642

RESUMO

KRAS mutation is the most frequent type of genetic mutation in non-small cell lung cancer (NSCLC), especially in lung adenocarcinoma. However, KRAS mutation can affect many biological processes and the mechanisms underlying KRAS mutation-mediate carcinogenesis in NSCLC have not been fully understood. In this research, we found that KRASG12C mutation was associated with the upregulation of T-LAK cell-originated protein kinase (TOPK), which is a well-known serine/threonine MAPK-like protein kinase implicated in tumorigenesis. The overexpression of TOPK significantly promoted the malignant phenotype of A549 cells, and TOPK silencing impaired the malignant phenotype with KRASG12C mutation. Moreover, we demonstrated that TOPK level was regulated by MAPK/ERK signalling and the transcription factor Elk1. TOPK was also found to promote the activation of NF-κB signalling in A549 cells with KRASG12C mutation via facilitating the phosphorylation of TAK1. In the in vivo tumorigenesis model, the administration of TOPK inhibitor OTS514 enhanced the anticancer effect of 5-FU, and the combinatory use of OTS514 and KRASG12C inhibitor AMG510 showed synergistic anti-tumour effect. These results suggest that KRAS-TOPK axis contributes to the progression of NSCLC and targeting this axis could synergize with anticancer effect of the existing chemotherapeutics.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinogênese/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células Matadoras Ativadas por Linfocina/metabolismo , Células Matadoras Ativadas por Linfocina/patologia , Neoplasias Pulmonares/patologia , Mutação/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
12.
J Biol Chem ; 298(6): 102020, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35537551

RESUMO

The aspariginyl hydroxylase human factor inhibiting hypoxia-inducible factor (FIH) is an important regulator of the transcriptional activity of hypoxia-inducible factor. FIH also catalyzes the hydroxylation of asparaginyl and other residues in ankyrin repeat domain-containing proteins, including apoptosis stimulating of p53 protein (ASPP) family members. ASPP2 is reported to undergo a single FIH-catalyzed hydroxylation at Asn-986. We report biochemical and crystallographic evidence showing that FIH catalyzes the unprecedented post-translational hydroxylation of both asparaginyl residues in "VNVN" and related motifs of ankyrin repeat domains in ASPPs (i.e., ASPP1, ASPP2, and iASPP) and the related ASB11 and p18-INK4C proteins. Our biochemical results extend the substrate scope of FIH catalysis and may have implications for its biological roles, including in the hypoxic response and ASPP family function.


Assuntos
Repetição de Anquirina , Oxigenases de Função Mista , Proteínas Repressoras , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Proteínas Reguladoras de Apoptose , Catálise , Humanos , Hidroxilação , Hipóxia , Oxigenases de Função Mista/metabolismo , Proteínas Repressoras/metabolismo
13.
Plant Mol Biol ; 111(3): 291-307, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36469200

RESUMO

KEY MESSAGE: We identified a dosage-dependent dominant negative form of Sar1c, which confirms the essential role of COPII system in mediating ER export of storage proteins in rice endosperm. Higher plants accumlate large amounts of seed storage proteins (SSPs). However, mechanisms underlying SSP trafficking are largely unknown, especially the ER-Golgi anterograde process. Here, we showed that a rice glutelin precursor accumulation13 (gpa13) mutant exhibited floury endosperm and overaccumulated glutelin precursors, which phenocopied the reported RNAi-Sar1abc line. Molecular cloning revealed that the gpa13 allele encodes a mutated Sar1c (mSar1c) with a deletion of two conserved amino acids Pro134 and Try135. Knockdown or knockout of Sar1c alone caused no obvious phenotype, while overexpression of mSar1c resulted in seedling lethality similar to the gpa13 mutant. Transient expression experiment in tobacco combined with subcellular fractionation experiment in gpa13 demonstrated that the expression of mSar1c affects the subcellular distribution of all Sar1 isoforms and Sec23c. In addition, mSar1c failed to interact with COPII component Sec23. Conversely, mSar1c competed with Sar1a/b/d to interact with guanine nucleotide exchange factor Sec12. Together, we identified a dosage-dependent dominant negative form of Sar1c, which confirms the essential role of COPII system in mediating ER export of storage proteins in rice endosperm.


Assuntos
Oryza , Proteínas de Armazenamento de Sementes , Proteínas de Armazenamento de Sementes/metabolismo , Oryza/genética , Transporte Proteico/genética , Glutens/genética , Retículo Endoplasmático/metabolismo
14.
Clin Immunol ; 251: 109325, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37030526

RESUMO

Ischemia-reperfusion injury (IRI) is one of the most common complications in liver transplantation. METTL3 regulates inflammation and cellular stress response by modulating RNA m6A modification level. Here, the study aimed to investigate the role and mechanism of METTL3 in IRI after rat orthotopic liver transplantation. The total RNA m6A modification and METTL3 expression level was consistently down-regulated after 6 h or 24 h reperfusion in OLT, which is negatively associated with the hepatic cell apoptosis. Functionally, METTL3 pretreatment in donor significantly inhibited liver grafts apoptosis, improved liver function and depressed the proinflammatory cytokine/chemokine expression. Mechanistically, METTL3 inhibited apoptosis of grafts via upregulating HO-1. Moreover, m6A dot blot and MeRIP-qPCR assay revealed that METTL3 promoted HO-1 expression in an m6A-dependent manner. In vitro, METTL3 alleviated hepatocytes apoptosis by upregulating HO-1 under hypoxia/reoxygenation condition. Taken together, these findings demonstrate that METTL3 ameliorates rat OLT-stressed IRI by inducing HO-1 in an m6A-dependent manner, highlighting a potential target for IRI in liver transplantation.


Assuntos
Transplante de Fígado , Traumatismo por Reperfusão , Ratos , Animais , Transplante de Fígado/efeitos adversos , Fígado/metabolismo , Inflamação/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , RNA/metabolismo
15.
J Exp Bot ; 74(6): 1911-1925, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36638269

RESUMO

The sporopollenin polymer is a major component of the pollen exine. Fatty acid derivatives synthesized in the tapetum are among the precursors of sporopollenin. Progress has been made to understand sporopollenin metabolism in rice; however, the underlying molecular mechanisms remain elusive. We found that OsTKPR2 and OsTKPR1 share a similar expression pattern, and their coding proteins have a similar subcellular localization and enzyme activities towards reduced tetraketide α-pyrone and hydroxylated tetraketide α-pyrone. Unexpectedly, OsTKPR1pro:OsTKPR2-eGFP could not rescue the phenotype of ostkpr1-4. Three independent ostkpr2 mutant lines generated by CRISPR/Cas9 displayed reduced male fertility to various extents which were correlated with the severity of gene disruptions. Notably, the anther cuticle, Ubisch bodies, and pollen development were affected in the ostkpr2-1 mutant, where a thinner pollen exine was noticed. OsTKPR1 and OsTKPR2 were integrated into a metabolon including OsACOS12 and OsPKS2, which resulted in a significant increased enzymatic efficiency when both OsTKPR1 and OsTKPR2 were present, indicating the mutual dependence of OsTKPR2 and OsTKPR1 for their full biochemical activities. Thus, our results demonstrated that OsTKPR2 is required for anther and pollen development where an OsTKPR2-containing metabolon is functional during rice sporopollenin synthesis. Furthermore, the cooperation and possible functional divergence between OsTKPR2 and OsTKPR1 is also discussed.


Assuntos
Oryza , Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Oryza/metabolismo , Pironas/metabolismo , Regulação da Expressão Gênica de Plantas
16.
Plant Cell ; 32(3): 758-777, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31949008

RESUMO

Dense vesicles (DVs) are vesicular carriers, unique to plants, that mediate post-Golgi trafficking of storage proteins to protein storage vacuoles (PSVs) in seeds. However, the molecular mechanisms regulating the directional targeting of DVs to PSVs remain elusive. Here, we show that the rice (Oryza sativa) glutelin precursor accumulation5 (gpa5) mutant is defective in directional targeting of DVs to PSVs, resulting in discharge of its cargo proteins into the extracellular space. Molecular cloning revealed that GPA5 encodes a plant-unique phox-homology domain-containing protein homologous to Arabidopsis (Arabidopsis thaliana) ENDOSOMAL RAB EFFECTOR WITH PX-DOMAIN. We show that GPA5 is a membrane-associated protein capable of forming homodimers and that it is specifically localized to DVs in developing endosperm. Colocalization, biochemical, and genetic evidence demonstrates that GPA5 acts in concert with Rab5a and VPS9a to regulate DV-mediated post-Golgi trafficking to PSVs. Furthermore, we demonstrated that GPA5 physically interacts with a class C core vacuole/endosome tethering complex and a seed plant-specific VAMP727-containing R-soluble N-ethylmaleimide sensitive factor attachment protein receptor complex. Collectively, our results suggest that GPA5 functions as a plant-specific effector of Rab5a required for mediating tethering and membrane fusion of DVs with PSVs in rice endosperm.


Assuntos
Complexo de Golgi/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Armazenamento de Sementes/metabolismo , Endosperma/metabolismo , Glutens/metabolismo , Complexo de Golgi/ultraestrutura , Proteínas de Membrana/metabolismo , Modelos Biológicos , Mutação/genética , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas de Plantas/química , Ligação Proteica , Multimerização Proteica , Transporte Proteico , Proteínas de Armazenamento de Sementes/química , Vacúolos/metabolismo , Vacúolos/ultraestrutura
17.
Diabetes Obes Metab ; 25(12): 3578-3588, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37612876

RESUMO

AIM: To our knowledge, this is the first real-world study to investigate the safety and effectiveness of a glucagon-like peptide-1 receptor agonist in Chinese patients with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: This prospective, observational, post-marketing study conducted at 46 hospitals in China included adults with T2DM prescribed dulaglutide in routine clinical practice. The primary endpoint was the incidence of treatment-emergent adverse events (TEAEs) and serious AEs in patients who received ≥1 dose of dulaglutide, for up to 24 weeks. Exploratory endpoints included changes in patient-reported glycated haemoglobin (HbA1c) and body weight. Post hoc analyses and multivariate regression were also performed. RESULTS: From 20 January 2020 to 24 November 2021, 3291 patients received dulaglutide and entered the safety analysis. TEAEs were reported in 1333 (40.5%) patients; the most commonly reported were nausea (n = 193, 5.9%), diarrhoea (n = 183, 5.6%) and decreased appetite (n = 179, 5.4%). serious AEs were reported in 160 (4.9%) patients. TEAEs led to treatment discontinuation in 212 (6.4%) patients. The mean absolute change in HbA1c from baseline to week 24 was -1.65% (p < .001). Greater reductions in HbA1c at week 24 were observed in patients with T2DM duration ≤5 years (p = .002), baseline HbA1c ≥8.5% (p < .001), and without atherosclerotic cardiovascular disease (p = .002). The mean absolute change in body weight from baseline at week 24 was -2.62 kg (p < .001). CONCLUSION: Dulaglutide showed a safety profile consistent with previous reports and significantly reduced HbA1c in a real-world setting. These findings support the clinical use of dulaglutide and inform the individualized treatment of patients with T2DM in China.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Adulto , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Hemoglobinas Glicadas , População do Leste Asiático , Estudos Prospectivos , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Proteínas Recombinantes de Fusão/efeitos adversos , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Peso Corporal
18.
Arterioscler Thromb Vasc Biol ; 42(1): 35-48, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34758633

RESUMO

OBJECTIVE: Animal models of atherosclerosis are used extensively to interrogate molecular mechanisms in serial fashion. We tested whether a novel systems biology approach to integration of preclinical data identifies novel pathways and regulators in human disease. Approach and Results: Of 716 articles published in ATVB from 1995 to 2019 using the apolipoprotein E knockout mouse to study atherosclerosis, data were extracted from 360 unique studies in which a gene was experimentally perturbed to impact plaque size or composition and analyzed using Ingenuity Pathway Analysis software. TREM1 (triggering receptor expressed on myeloid cells) signaling and LXR/RXR (liver X receptor/retinoid X receptor) activation were identified as the top atherosclerosis-associated pathways in mice (both P<1.93×10-4, TREM1 implicated early and LXR/RXR in late atherogenesis). The top upstream regulatory network in mice (sc-58125, a COX2 inhibitor) linked 64.0% of the genes into a single network. The pathways and networks identified in mice were interrogated by testing for associations between the genetically predicted gene expression of each mouse pathway-identified human homolog with clinical atherosclerosis in a cohort of 88 660 human subjects. Homologous human pathways and networks were significantly enriched for gene-atherosclerosis associations (empirical P<0.01 for TREM1 and LXR/RXR pathways and COX2 network). This included 12(60.0%) TREM1 pathway genes, 15(53.6%) LXR/RXR pathway genes, and 67(49.3%) COX2 network genes. Mouse analyses predicted, and human study validated, the strong association of COX2 expression (PTGS2) with increased likelihood of atherosclerosis (odds ratio, 1.68 per SD of genetically predicted gene expression; P=1.07×10-6). CONCLUSIONS: PRESCIANT (Preclinical Science Integration and Translation) leverages published preclinical investigations to identify high-confidence pathways, networks, and regulators of human disease.


Assuntos
Apolipoproteínas E/genética , Aterosclerose/genética , Redes Reguladoras de Genes , Biologia de Sistemas , Adulto , Idoso , Animais , Apolipoproteínas E/deficiência , Aterosclerose/metabolismo , Aterosclerose/patologia , Modelos Animais de Doenças , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Camundongos Knockout para ApoE , Pessoa de Meia-Idade , Fenótipo , Placa Aterosclerótica , Medição de Risco , Fatores de Risco , Fatores Sexuais , Especificidade da Espécie
19.
BMC Infect Dis ; 23(1): 632, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37759271

RESUMO

BACKGROUND: Influenza is a common illness for its high rates of morbidity and transmission. The implementation of non-pharmaceutical interventions (NPIs) during the COVID-19 pandemic to manage its dissemination could affect the transmission of influenza. METHODS: A retrospective analysis, between 2018 and 2023, was conducted to examine the incidence of influenza virus types A and B among patients in sentinel cities located in North or South China as well as in Wuhan City. For validations, data on the total count of influenza patients from 2018 to 2023 were collected at the Central Hospital of Wuhan, which is not included in the sentinel hospital network. Time series methods were utilized to examine seasonal patterns and to forecast future influenza trends. RESULTS: Northern and southern cities in China had earlier outbreaks during the NPIs period by about 8 weeks compared to the 2018-2019. The implementation of NPIs significantly reduced the influenza-like illness (ILI) rate and infection durations. Influenza B Victoria and H3N2 were the first circulating strains detected after the relaxation of NPIs, followed by H1N1 across mainland China. The SARIMA model predicted synchronized H1N1 outbreak cycles in North and South China, with H3N2 expected to occur in the summer in southern cities and in the winter in northern cities over the next 3 years. The ILI burden is expected to rise in both North and South China over the next 3 years, with higher ILI% levels in southern cities throughout the year, especially in winter, and in northern cities mainly during winter. In Wuhan City and the Central Hospital of Wuhan, influenza levels are projected to peak in the winter of 2024, with 2 smaller peaks expected during the summer of 2023. CONCLUSIONS: In this study, we report the impact of NPIs on future influenza trends in mainland China. We recommend that local governments encourage vaccination during the transition period between summer and winter to mitigate economic losses and mortality associated with influenza.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Humanos , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vírus da Influenza A Subtipo H3N2 , Pandemias/prevenção & controle , Estudos Retrospectivos , China/epidemiologia
20.
Mikrochim Acta ; 191(1): 52, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-38147136

RESUMO

Coconut cadang-cadang viroid (CCCVd) is an infectious single-stranded RNA (ssRNA) pathogen, which leads directly to the death of a large number of coconut palm trees and heavy economic loss to coconut farmers. Herein, a novel electrochemical impedance RNA genosensor is presented based on highly stable gold nanoparticles (AuNPs) decorated phosphorene (BP) nanohybrid with graphene (Gr) for highly sensitive, low-cost, and label-free detection of CCCVd. BP-AuNPs are environmentally friendly prepared by ultrasonic-assisted liquid-phase exfoliation of black phosphorus, accompanying direct reduction of chloroauric acid. Gr/BP-AuNPs are facilely prepared by the in situ growth of AuNPs onto the BP surface and its nanohybrid with Gr to improve environmental stability of BP. Gr/BP-AuNP-based RNA genosensor is fabricated by immobilizing the thiol-functionalized single-stranded DNA (ssDNA) oligonucleotide probe onto the surface of Gr/BP-AuNP-modified glassy carbon electrode via gold-thiol interactions, which served as an electrochemical genosensing platform for the label-free impedance detection of CCCVd by hybridization between the functionalized ssDNA probe and the complementary CCCVd ssRNA sequence in a wide linear range from 1.0 × 10-11 to 1.0 × 10-7 M with a low limit of detection of 2.8 × 10-12 M. This work supplies an experimental support and theoretical direction for the fabrication of RNA biosensors based on graphene-like materials and potential application for a specific diagnosis of plant RNA viral disease in Arecaceae planting industry.


Assuntos
Grafite , Nanopartículas Metálicas , Ouro , DNA de Cadeia Simples , Compostos de Sulfidrila
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