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1.
New Phytol ; 233(1): 265-281, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34637530

RESUMO

Protein bodies (PBs), the major protein storage organelle in maize (Zea mays) endosperm, comprise zeins and numerous nonzein proteins (NZPs). Unlike zeins, how NZPs accumulate in PBs remains unclear. We characterized a maize miniature kernel mutant, mn*, that produces small kernels and is embryo-lethal. After cloning the Mn* locus, we determined that it encodes the mitochondrial 50S ribosomal protein L10 (mRPL10). MN* localized to mitochondria and PBs as an NZP; therefore, we renamed MN* Non-zein Protein 1 (NZP1). Like other mutations affecting mitochondrial proteins, mn* impaired mitochondrial function and morphology. To investigate its accumulation mechanism to PBs, we performed protein interaction assays between major zein proteins and NZP1, and found that NZP1 interacts with 22 kDa α-zein. Levels of NZP1 and 22 kDa α-zein in various opaque mutants were correlated. Furthermore, NZP1 accumulation in induced PBs depended on its interaction with 22 kDa α-zein. Comparative proteomic analysis of PBs between wild-type and opaque2 revealed additional NZPs. A new NZP with plastidial localization was also found to accumulate in induced PBs via interaction with 22 kDa α-zein. This study thus reveals a mechanism for accumulation of NZPs in PBs and suggests a potential application for the accumulation of foreign proteins in maize PBs.


Assuntos
Endosperma , Zeína , Organelas , Proteínas de Plantas/genética , Proteômica , Sementes , Zea mays/genética , Zeína/genética
2.
BMC Vet Res ; 14(1): 299, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30285759

RESUMO

BACKGROUND: In the host immune system, perforin is a cytotoxic effector molecule that eliminate virus-infected and malignant cells. Moreover, some recent studies also imply the involvement of perforin in antibacterial immunity. Common carp (Cyprinus carpio L.), one of the most economically important fish species in China, has a high susceptibility to viruses and bacteria. Thus far, in common carp, no data are available regarding the identification and immunologic function of the perforin. RESULTS: In the present study, the cDNA and genomic DNA sequences of three perforin isoform genes were cloned and characterized in common carp, named CcPRF1, CcPRF2 and CcPRF3. Amino acid sequences of the three CcPRFs were quite different, with identities ranged from 37.3 to 39.5%. Phylogenetic analysis showed that three CcPRFs, each in a separate sub-branch, possessed closer evolutionary relationship with other teleost perforins, especially with cyprinid fishes, than higher vertebrates. Expression analysis revealed that each CcPRF gene was differentially expressed in all of the nine tested tissues. During larvae ontogeny, each CcPRF displayed a distinct expression pattern, while with a common expression peak at 22 days post hatching (dph). Moreover, in vivo or in vitro, after stimulation with polyI:C, LPS and Aeromonas hydrophila, each CcPRF was induced significantly, with differential expression dynamics. CONCLUSIONS: Our findings suggest that perforin might play significant roles in larval immune system and in the immune defense of common carp against viral and bacterial pathogens. Meantime, the differential expression dynamics seem to imply possible different cellular locations or functional differences across various CcPRF isoforms.


Assuntos
Carpas/crescimento & desenvolvimento , Carpas/imunologia , Perforina/química , Aeromonas hydrophila/imunologia , Sequência de Aminoácidos , Animais , Carpas/metabolismo , Perfilação da Expressão Gênica , Larva/crescimento & desenvolvimento , Larva/imunologia , Larva/metabolismo , Lipopolissacarídeos/administração & dosagem , Perforina/genética , Perforina/metabolismo , Filogenia , Poli I-C/administração & dosagem , Análise de Sequência de DNA
3.
J Sep Sci ; 41(5): 1025-1038, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29227021

RESUMO

Tangzhiqing formula, a Chinese herbal formula, is used for the treatment of type II diabetes and prediabetes. Although its effectiveness has been certified by clinical use, its absorbed chemical constituents are not comprehensively represented. Thence, in order to reveal potential bioactive components and metabolism of Tangzhiqing formula, an ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry method was developed. A total of 86 absorbed components, including 38 prototype compounds and 48 metabolites, were identified in rat plasma, urine, and feces after oral administration of Tangzhiqing formula. This was the first systematic study on the chemical constituents and metabolic profiling of Tangzhiqing formula. The results indicated that alkaloids and flavonoids were main absorbed components, and glucuronidation and sulfation were the major metabolites. Moreover we concluded that alkaloids and flavonoids first underwent demethylation and hydrolysis reactions before biotransformed to phase II metabolites. This study provided valuable data for safety estimation of Tangzhiqing formula, which will be advantageous for clinical application.


Assuntos
Medicamentos de Ervas Chinesas/análise , Administração Oral , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/metabolismo , Espectrometria de Massas , Estrutura Molecular , Fatores de Tempo
4.
Biomed Chromatogr ; 31(12)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28556969

RESUMO

Quercetin, a kind of major flavonoid found in many traditional chinese medicines, is an effective substance for treatments such as lowering blood lipids. However, the studies on quercetin have been mainly focused on its pharmacological effect; the treatment of diseases on a material basis, particularly the metabolites derived from quercetin in vivo, has not been evaluated. In this study, we determined the levels, distributions and types of quercetin's metabolites in plasma, urine, feces and bile of rats after a single oral administration of quercetin at a dose of 80 mg/kg, using ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS). A total of 36 metabolites of quercetin were identified, including 11 metabolites in plasma, 34 metabolites in urine, 12 metabolites in feces and 21 metabolites in bile. The results showed that phase I metabolites were reduction metabolites and phase II metabolites mainly included glucuronidation, sulfation and methylation metabolites. These results provide important information on the metabolism of quercetin, which will be helpful for its further development and utilization.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Metabolômica/métodos , Quercetina/análise , Quercetina/metabolismo , Administração Oral , Animais , Masculino , Quercetina/administração & dosagem , Quercetina/química , Ratos , Ratos Wistar
5.
IEEE Trans Pattern Anal Mach Intell ; 45(2): 2627-2644, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35471873

RESUMO

Face benchmarks empower the research community to train and evaluate high-performance face recognition systems. In this paper, we contribute a new million-scale recognition benchmark, containing uncurated 4M identities/260M faces (WebFace260M) and cleaned 2M identities/42M faces (WebFace42M) training data, as well as an elaborately designed time-constrained evaluation protocol. First, we collect 4M name lists and download 260M faces from the Internet. Then, a Cleaning Automatically utilizing Self-Training (CAST) pipeline is devised to purify the tremendous WebFace260M, which is efficient and scalable. To the best of our knowledge, the cleaned WebFace42M is the largest public face recognition training set and we expect to close the data gap between academia and industry. Referring to practical deployments, Face Recognition Under Inference Time conStraint (FRUITS) protocol and a new test set with rich attributes are constructed. Besides, we gather a large-scale masked face sub-set for biometrics assessment under COVID-19. For a comprehensive evaluation of face matchers, three recognition tasks are performed under standard, masked and unbiased settings, respectively. Equipped with this benchmark, we delve into million-scale face recognition problems. A distributed framework is developed to train face recognition models efficiently without tampering with the performance. Enabled by WebFace42M, we reduce 40% failure rate on the challenging IJB-C set and rank 3rd among 430 entries on NIST-FRVT. Even 10% data (WebFace4M) shows superior performance compared with the public training sets. Furthermore, comprehensive baselines are established under the FRUITS-100/500/1000 milliseconds protocols. The proposed benchmark shows enormous potential on standard, masked and unbiased face recognition scenarios. Our WebFace260M website is https://www.face-benchmark.org.


Assuntos
COVID-19 , Reconhecimento Facial , Humanos , Benchmarking , Algoritmos , Face
6.
Nat Commun ; 14(1): 8163, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38071210

RESUMO

Cultured meat production has emerged as a breakthrough technology for the global food industry with the potential to reduce challenges associated with environmental sustainability, global public health, animal welfare, and competition for food between humans and animals. The muscle stem cell lines currently used for cultured meat cannot be passaged in vitro for extended periods of time. Here, we develop a directional differentiation system of porcine pre-gastrulation epiblast stem cells (pgEpiSCs) with stable cellular features and achieve serum-free myogenic differentiation of the pgEpiSCs. We show that the pgEpiSCs-derived skeletal muscle progenitor cells and skeletal muscle fibers have typical muscle cell characteristics and display skeletal muscle transcriptional features during myogenic differentiation. Importantly, we establish a three-dimensional differentiation system for shaping cultured tissue by screening plant-based edible scaffolds of non-animal origin, followed by the generation of pgEpiSCs-derived cultured meat. These advances provide a technical approach for the development of cultured meat.


Assuntos
Músculo Esquelético , Células-Tronco , Humanos , Animais , Suínos , Músculo Esquelético/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Diferenciação Celular , Carne , Células Cultivadas
7.
IEEE Trans Biomed Circuits Syst ; 17(5): 1177, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37988218

RESUMO

In [1], this paper was submitted for the Special Issue on Flexible Biomedical Sensors for Healthcare Applications. The paper was instead published in Volume 16, Issue 6, 2022.

8.
IEEE Trans Biomed Circuits Syst ; 16(6): 1337-1347, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36094965

RESUMO

This paper provides a special flexible graphene film based capacitive wireless power transfer (FGCPT) system for powering biomedical sensors of smart wearable devices. The graphene conductive material is flexible, transparent, highly conductive, and impermeable to most gases and liquids. Generally, the coupling structure of capacitive wireless power transfer (CPT) system is consisted of metal plates. However, it is hard to use for the biomedical sensors as the low power density and big volume. The shape of graphene conductive material could be easily built and changed according to the application requirements. In this paper, the power supply of biomedical sensing system could be accomplished by a single graphene film which is acted as the receiver of FGCPT system. The 200 mW power level is achieved with the maximum 9 V output voltage. The theory and calculation are verified by the simulated and experimental results.


Assuntos
Grafite , Dispositivos Eletrônicos Vestíveis , Grafite/química , Fontes de Energia Elétrica , Instalação Elétrica , Condutividade Elétrica
9.
Cell Res ; 32(4): 383-400, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34848870

RESUMO

Pig epiblast-derived pluripotent stem cells are considered to have great potential and broad prospects for human therapeutic model development and livestock breeding. Despite ongoing attempts since the 1990s, no stably defined pig epiblast-derived stem cell line has been established. Here, guided by insights from a large-scale single-cell transcriptome analysis of pig embryos from embryonic day (E) 0 to E14, specifically, the tracing of pluripotency changes during epiblast development, we developed an in vitro culture medium for establishing and maintaining stable pluripotent stem cell lines from pig E10 pregastrulation epiblasts (pgEpiSCs). Enabled by chemical inhibition of WNT-related signaling in combination with growth factors in the FGF/ERK, JAK/STAT3, and Activin/Nodal pathways, pgEpiSCs maintain their pluripotency transcriptome features, similar to those of E10 epiblast cells, and normal karyotypes after more than 240 passages and have the potential to differentiate into three germ layers. Strikingly, ultradeep in situ Hi-C analysis revealed functional impacts of chromatin 3D-spatial associations on the transcriptional regulation of pluripotency marker genes in pgEpiSCs. In practice, we confirmed that pgEpiSCs readily tolerate at least three rounds of successive gene editing and generated cloned gene-edited live piglets. Our findings deliver on the long-anticipated promise of pig pluripotent stem cells and open new avenues for biological research, animal husbandry, and regenerative biomedicine.


Assuntos
Camadas Germinativas , Células-Tronco Pluripotentes , Animais , Diferenciação Celular/genética , Linhagem Celular , Suínos , Transcriptoma
10.
Cell Death Dis ; 12(11): 989, 2021 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-34689175

RESUMO

Proper follicle development is very important for the production of mature oocytes, which is essential for the maintenance of female fertility. This complex biological process requires precise gene regulation. The most abundant modification of mRNA, N6-methyladenosine (m6A), is involved in many RNA metabolism processes, including RNA splicing, translation, stability, and degradation. Here, we report that m6A plays essential roles during oocyte and follicle development. Oocyte-specific inactivation of the key m6A methyltransferase Mettl3 with Gdf9-Cre caused DNA damage accumulation in oocytes, defective follicle development, and abnormal ovulation. Mechanistically, combined RNA-seq and m6A methylated RNA immunoprecipitation sequencing (MeRIP-seq) data from oocytes revealed, that we found METTL3 targets Itsn2 for m6A modification and then enhances its stability to influence the oocytes meiosis. Taken together, our findings highlight the crucial roles of mRNA m6A modification in follicle development and coordination of RNA stabilization during oocyte growth.


Assuntos
Adenosina/análogos & derivados , Metiltransferases/metabolismo , Oócitos/metabolismo , Folículo Ovariano/crescimento & desenvolvimento , Adenosina/metabolismo , Animais , Feminino , Camundongos
11.
Stem Cell Res Ther ; 11(1): 67, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070424

RESUMO

BACKGROUND: NANOG functions as the gateway for the generation of pluripotent stem cells (PSCs) in mice and humans. NANOG is a transcription factor highly expressed in pig pre-implantation embryos, indicating that it is a conserved pluripotency-associated factor. However, pig NANOG reporter PSCs have yet to be established, and the regulation of pluripotency by NANOG is not fully understood in this animal. METHODS: In this study, pig NANOG tdTomato knock-in reporter positive PC-iPS cells were established using CRISPR/Cas9. The resulting cell line was treated with several cytokines and their corresponding inhibitors to identify pathways that regulate NANOG expression. The pathways examined were LIF (leukemia inhibitory factor)/IL6 (interleukin 6)-STAT3, FGF (fibroblast growth factor)/ERK, IGF1 (insulin-like growth factor 1)/PIP3 (phosphoinositide 3-kinase)-AKT, Activin A/SMAD, and BMP4 (bone morphogenetic proteins)/SMAD. RESULTS: Our experiments showed that the Activin A/SMAD pathway is directly associated with activation of NANOG expression in the pig, as is also the case in mice and humans. Activin A directly regulates the expression of pig NANOG via SMAD2/3; inhibition of this pathway by SB431542 resulted in inhibition of NANOG expression. CONCLUSIONS: Our results show that Activin A plays an important regulatory role in NANOG-mediated pluripotency in pig iPS cells. Activin A treatment may be therefore an effective method for de novo derivation of authentic embryonic stem cells (ESCs) from pig pre-implantation embryos.


Assuntos
Ativinas/metabolismo , Sistemas CRISPR-Cas/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteína Homeobox Nanog/metabolismo , Células-Tronco Pluripotentes/metabolismo , Animais , Diferenciação Celular , Humanos , Transdução de Sinais , Suínos
12.
Genetics ; 205(4): 1489-1501, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28213476

RESUMO

Respiration, the core of mitochondrial metabolism, depends on the function of five respiratory complexes. Many respiratory chain-related proteins are encoded by the mitochondrial genome and their RNAs undergo post-transcriptional modifications by nuclear genome-expressed factors, including pentatricopeptide repeat (PPR) proteins. Maize defective kernel 10 (dek10) is a classic mutant with small kernels and delayed development. Through positional cloning, we found that Dek10 encodes an E-subgroup PPR protein localized in mitochondria. Sequencing analysis indicated that Dek10 is responsible for the C-to-U editing at nad3-61, nad3-62, and cox2-550 sites, which are specific editing sites in monocots. The defects of these editing sites result in significant reduction of Nad3 and the loss of Cox2. Interestingly, the assembly of complex I was not reduced, but its NADH dehydrogenase activity was greatly decreased. The assembly of complex IV was significantly reduced. Transcriptome and transmission electron microscopy (TEM) analysis revealed that proper editing of nad3 and cox2 is critical for mitochondrial functions, biogenesis, and morphology. These results indicate that the E-subgroup PPR protein Dek10 is responsible for multiple editing sites in nad3 and cox2, which are essential for mitochondrial functions and plant development in maize.


Assuntos
Mitocôndrias/genética , Edição de RNA , Zea mays/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
13.
Zhongguo Zhen Jiu ; 37(3): 297-300, 2017 Mar 12.
Artigo em Chinês | MEDLINE | ID: mdl-29231438

RESUMO

OBJECTIVE: To observe the clinical effect differences between infraoccipital needle-knife and massage for cervical vertigo. METHODS: A total of 366 patients with cervical vertigo were randomly assigned into a needle-knife group (186 cases) and a massage group (180 cases). With cases dropping excluded, 183 cases in the needle-knife group and 176 cases in the massage group were included. Needle-knife was used at Fengchi (GB 20), infraoccipital ashi point, etc. in the needle-knife group. The treatment was given for one course, once three days, 5 times as one course. The traditional massage was applied in the massage group for one course, including systematic stroking, kneading, and the application of pressure and plucking, etc., once every two days and 7 times as one course. The dizziness handicap inventory (DHI) score was observed before and after treatment, as well as 3, 6, and 12 months after treatment. The effects were also evaluated. RESULTS: The total effective rate was 92.3% (169/183) in the needle-knife group, which was better than 85.2% (150/176) in the massage group (P<0.05). Compared with those before treatment, the DHI scores at all the observation time points after treatment were improved in the two groups (all P<0.05), with better improvements after treatment as well as 3 and 6 months after treatment in the needle-knife group (all P<0.05). There was no significant difference in the improvement of DHI scores between the two groups 12 months after treatment (P>0.05). The recurrence rate was 10.3% (12/117) in the needle-knife group, and it was 10.7% (11/103) in the massage group 12 months after treatment (P>0.05). CONCLUSIONS: Infraoccipital needle-knife achieves apparent effect for cervical vertigo, which is superior to massage in short period.


Assuntos
Terapia por Acupuntura/métodos , Massagem , Vertigem/terapia , Pontos de Acupuntura , Humanos , Agulhas
14.
Mol Plant ; 10(3): 427-441, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-27596292

RESUMO

In higher plants, the splicing of organelle-encoded mRNA involves a complex collaboration with nuclear-encoded proteins. Pentatricopeptide repeat (PPR) proteins have been implicated in these RNA-protein interactions. In this study, we performed the cloning and functional characterization of maize Defective kernel 35 (Dek35). The dek35-ref mutant is a lethal-seed mutant with developmental deficiency. Dek35 was cloned through Mutator tag isolation and further confirmed by four additional independent mutant alleles. Dek35 encodes an P-type PPR protein that targets the mitochondria. The dek35 mutation causes significant reduction in the accumulation of DEK35 proteins and reduced splicing efficiency of mitochondrial nad4 intron 1. Analysis of mitochondrial complex in dek35 immature seeds indicated severe deficiency in the complex I assembly and NADH dehydrogenase activity. Transcriptome analysis of dek35 endosperm revealed enhanced expression of genes involved in the alternative respiratory pathway and extensive differentially expressed genes related to mitochondrial function and activity. Collectively, these results indicate that Dek35 encodes an PPR protein that affects the cis-splicing of mitochondrial nad4 intron 1 and is required for mitochondrial function and seed development.


Assuntos
Íntrons/genética , Proteínas Mitocondriais/metabolismo , Sementes/metabolismo , Zea mays/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , NAD/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Splicing de RNA/genética , Splicing de RNA/fisiologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Zea mays/genética , Zea mays/crescimento & desenvolvimento
15.
J Pharm Biomed Anal ; 140: 71-80, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28342305

RESUMO

Nuciferine, a major alkaloid found in Nelumbinis Folium, exhibits a broad spectrum of bioactivities, such as antiobesity, anti-diabetes and anti-inflammatory. However, many research regarding nuciferine focused on the extraction, isolation and biological activity, the metabolism is not comprehensively explained in vivo. Thence, the present of this paper is to establish a simple method for speculating metabolites of nuciferine. A total of 15 metabolites were detected and tentatively identified through ultra high performance liquid chromatography-diode array detection-quadrupole time-of-flight mass spectrometry (UHPLC-DAD-QTOF-MS), including 7 new metabolites. Among them, we also discovered a previously unmentioned metabolically active site at the C1-OCH3 position. These metabolites suggested that demethylation, oxidation, glucuronidation and sulfation were major metabolic pathways. This study provided significant experiment basis for its safety estimate and valuable information about the metabolism of nuciferine, which will be advantageous for new drug development.


Assuntos
Espectrometria de Massas , Administração Oral , Animais , Aporfinas , Bile , Cromatografia Líquida de Alta Pressão , Fezes , Ratos
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