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1.
Heliyon ; 10(16): e36376, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39258214

RESUMO

Quantitative Magnetic Resonance Imaging (qMRI) offers precise measurements of the relaxation characteristics of microstructures, representing a cutting-edge method in non-destructive fruit analysis. This study aims to visualize information on changes in moisture status and distribution at the subcellular level of winter jujube. The 0.5 T nuclear magnetic imaging equipment was utilized to rapidly, non-invasively, and accurately capture the internal relaxation status of the sample with multiple-echo-imaging. By examining the signal and noise data, a simulated dataset was developed to tackle the optimization challenge of estimating parameters for the discrete relaxation model from the multiple-echo-imaging data, especially under conditions of low signal-to-noise ratio (SNR) and in the context of heteroscedastic noise. An optimal weighting factor and the T2NR truncation model have been identified to establish an effective experimental inversion strategy. Subsequently, multiple-echo-imaging can rapidly and stably yielded voxel-level maps under conditions of low signal-to-noise ratio. Utilizing this experimental approach, data from winter jujube was collected and analyzed, facilitating an exploration of water activity (T2 mapping) and associated water content (A2 mapping). Through analyzing winter jujube fruits across two maturity stages, this study elucidates the role of precise quantification and voxel-wise visualization in moisture status detection. The methodology presents an innovative approach for assessing internal moisture distribution in fruits.

2.
J Agric Food Chem ; 72(35): 19413-19423, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39178398

RESUMO

Chicken is the main source of protein for humans in most parts of the world. However, excessive fat deposition in chickens has become a serious problem. This adversely affects the growth of chickens and causes economic losses. Fat formation mainly occurs through preadipocyte differentiation, and excessive fat deposition results from the accumulation of preadipocytes after differentiation. Our previous studies have found that the connective tissue growth factor (CTGF) may be an important candidate gene for fat deposition. However, its function and mechanism in preadipocyte differentiation are still unclear. In this study, the RT-qPCR and Western blot results showed that the expression of CTGF mRNA and protein in the abdominal adipose of lean chickens was significantly higher than that of fat chickens. Therefore, we studied the function and mechanism of the CTGF in the differentiation of chicken preadipocytes. Functionally, the CTGF inhibited the differentiation of chicken preadipocytes. Mechanistically, the CTGF mediated the TGFß1/Smad3 signaling pathway, thereby inhibiting the differentiation of chicken preadipocytes. In addition, we used the unique molecular identifier (UMI) RNA-Seq technology to detect genes that can be regulated by the CTGF in the whole genome. Through transcriptome data analysis, we selected actin gamma 2 (ACTG2) as a candidate gene. Regarding the function of the ACTG2 gene, we found that it inhibited the differentiation of chicken preadipocytes. Furthermore, we found that the CTGF can inhibit the differentiation of preadipocytes through the ACTG2 gene. In summary, this study found the CTGF as a new negative regulator of chicken preadipocyte differentiation. The results of this study help improve the understanding of the molecular genetic mechanism of chicken adipose tissue growth and development and also have reference significance for the study of human obesity.


Assuntos
Adipócitos , Diferenciação Celular , Galinhas , Fator de Crescimento do Tecido Conjuntivo , Transdução de Sinais , Proteína Smad3 , Animais , Galinhas/genética , Galinhas/metabolismo , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Adipócitos/metabolismo , Adipócitos/citologia , Proteína Smad3/metabolismo , Proteína Smad3/genética , Adipogenia , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/genética
3.
Animals (Basel) ; 14(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38275813

RESUMO

As an excellent chicken breed found in a high-altitude zone of northern China, Lindian chickens are characterized by good egg and meat production, strong adaptability, cold tolerance, rough feeding resistance, excellent egg quality, and delicious meat quality. To facilitate the exploitation of the unique qualities of the Lindian chicken, the varying patterns and correlations of various body size and carcass traits of 3-22-week-old Lindian chickens were analyzed in this study. The optimal growth model of these traits was determined by growth curve fitting analysis. The results showed that most traits of Lindian chickens increased steadily with increasing age, and most of them increased rapidly before 10 weeks of age. In addition, the inflection point age of each trait was predicted to be between 4 and 10 weeks. Furthermore, this study revealed that body size traits were closely related to carcass traits in Lindian chickens. In summary, Lindian chickens are in a rapid growth stage before the age of 10 weeks, and better slaughter performance can be achieved through good feeding management during this stage. The reproductive traits and muscles are the main developmental focus after the age of 19 weeks, so it is important to adequately meet their energy requirements for subsequent good breeding performance.

4.
Poult Sci ; 103(1): 103250, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992620

RESUMO

The deposition of high levels of fat in broiler breeder hens can have a profound impact on follicular development and laying performance. This study was formulated with the goal of comparing egg production and follicular development characteristics at different laying stages in the Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF). The egg production was analyzed using the birds from the 19th to 24th generations of NEAUHLF; the follicular development characteristics were analyzed by hematoxylin-eosin staining and quantitative real-time polymerase chain reaction using the birds from the 24th generation of NEAUHLF. The results showed that the age at first egg of lean hens was significantly earlier than that of fat hens in this study. While no significant differences in total egg output from the first egg to 50 wk of age were noted when comparing these 2 chicken lines, lean hens laid more eggs from the first egg to 35 wk of age relative to fat hens, whereas fat hens laid more eggs from wk 36 to 42 and 43 to 50 relative to their lean counterparts. No differences in ovarian morphology and small yellow follicle (SYF) histological characteristics were noted when comparing these 2 chicken lines at 27 wk of age. At 35 and 52 wk of age, however, lean hens exhibited significantly lower ovarian weight, ovarian proportion values, numbers of hierarchical follicles, hierarchical follicle weight, and SYF granulosa layer thickness as compared to fat hens, together with a significant increase in the number of prehierarchical follicles relative to those in fat hens. Gene expression analyses suggested that follicle selection was impaired in the fat hens in the early laying stage, whereas both follicle selection and maturation were impaired in the lean hens in the middle and late laying stages. Overall, these data highlight that fat deposition in broiler hens can have a range of effects on follicular development and egg production that are laying stage-dependent.


Assuntos
Galinhas , Óvulo , Humanos , Animais , Feminino , Galinhas/genética , Folículo Ovariano , Ovário/anatomia & histologia , Oviposição
5.
Int J Biol Macromol ; 256(Pt 2): 128414, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029903

RESUMO

Preadipocyte proliferation is an essential process in adipose development. During proliferation of preadipocytes, transcription factors play crucial roles. HMG-box protein 1 (HBP1) is an important transcription factor of cellular proliferation. However, the function and underlying mechanisms of HBP1 in the proliferation of preadipocytes remain unclear. Here, we found that the expression level of HBP1 decreased first and then increased during the proliferation of chicken preadipocytes. Knockout of HBP1 could inhibit the proliferation of preadipocytes, while overexpression of HBP1 could promote the proliferation of preadipocytes. ChIP-seq data showed that HBP1 had the unique DNA binding motif in chicken preadipocytes. By integrating ChIP-Seq and RNA-Seq, we revealed a total of 3 candidate target genes of HBP1. Furthermore, the results of ChIP-qPCR, RT-qPCR, luciferase reporter assay and EMSA showed that HBP1 could inhibit the transcription of suppressor of cytokine signaling 3 (SOCS3) by binding to its promoter. Moreover, we confirmed that SOCS3 can mediate the regulation of HBP1 on the proliferation of preadipocytes through RNAi and rescue experiments. Altogether, these data demonstrated that HBP1 directly targets SOCS3 to regulate chicken preadipocyte proliferation. Our findings expand the transcriptional regulatory network of preadipocyte proliferation, and they will be helpful in formulating a molecular breeding scheme to control excessive abdominal fat deposition and to improve meat quality in chickens.


Assuntos
Galinhas , Fatores de Transcrição , Animais , Galinhas/metabolismo , Fatores de Transcrição/genética , Interferência de RNA , Proliferação de Células/genética
6.
Food Chem ; 438: 137631, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37983998

RESUMO

The development of biosensors capable of assessing umami intensity has elicited significant attention. However, the detection range of these biosensors is constrained by the sensing components and strategies used. In this study, we introduce a novel competitive, ultra-high-sensitivity impedance biosensor by utilizing composite nanomaterials and T1R1 as a composite signal probe. Pd/Cu-TCPP(Fe) had a substantial surface area, effectively enhancing the loading capacity of the T1R1 and thus augmenting the biosensor's recognition precision. Furthermore, the Pd/Cu-TCPP(Fe) elevated peroxidase-like activity catalyzed the formation of insoluble precipitates of 4-chloro-1-naphthol (4-CN), resulting in cascaded amplification of the impedance signal. The remarkable catalytic activity of the composite signal probe endowed the biosensor with exceptional analytical performance, featuring a limit of detection (LOD) of 0.86 pg/mL and a linear detection range spanning from 10 to 10,000 pg/mL. Successful application of the biosensor for umami detection in fish was demonstrated, signifying its substantial potential in food-flavor evaluation.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Impedância Elétrica , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Limite de Detecção , Antioxidantes
7.
Nature ; 615(7952): 526-534, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36890225

RESUMO

The nucleolus is the most prominent membraneless condensate in the nucleus. It comprises hundreds of proteins with distinct roles in the rapid transcription of ribosomal RNA (rRNA) and efficient processing within units comprising a fibrillar centre and a dense fibrillar component and ribosome assembly in a granular component1. The precise localization of most nucleolar proteins and whether their specific localization contributes to the radial flux of pre-rRNA processing have remained unknown owing to insufficient resolution in imaging studies2-5. Therefore, how these nucleolar proteins are functionally coordinated with stepwise pre-rRNA processing requires further investigation. Here we screened 200 candidate nucleolar proteins using high-resolution live-cell microscopy and identified 12 proteins that are enriched towards the periphery of the dense fibrillar component (PDFC). Among these proteins, unhealthy ribosome biogenesis 1 (URB1) is a static, nucleolar protein that ensures 3' end pre-rRNA anchoring and folding for U8 small nucleolar RNA recognition and the subsequent removal of the 3' external transcribed spacer (ETS) at the dense fibrillar component-PDFC boundary. URB1 depletion leads to a disrupted PDFC, uncontrolled pre-rRNA movement, altered pre-rRNA conformation and retention of the 3' ETS. These aberrant 3' ETS-attached pre-rRNA intermediates activate exosome-dependent nucleolar surveillance, resulting in decreased 28S rRNA production, head malformations in zebrafish and delayed embryonic development in mice. This study provides insight into functional sub-nucleolar organization and identifies a physiologically essential step in rRNA maturation that requires the static protein URB1 in the phase-separated nucleolus.


Assuntos
Nucléolo Celular , Exossomos , Precursores de RNA , Processamento Pós-Transcricional do RNA , RNA Ribossômico , Peixe-Zebra , Animais , Camundongos , Nucléolo Celular/metabolismo , Desenvolvimento Embrionário , Exossomos/metabolismo , Cabeça/anormalidades , Microscopia , Proteínas Nucleares/metabolismo , Precursores de RNA/metabolismo , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , RNA Ribossômico 28S/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
8.
Chem Sci ; 13(30): 8797-8803, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35975146

RESUMO

The rational design of efficient catalysts for electrochemical water oxidation highly depends on the understanding of reaction pathways, which still remains a challenge. Herein, mononuclear and binuclear cobalt phthalocyanine (mono-CoPc and bi-CoPc) with a well-defined molecular structure are selected as model electrocatalysts to study the water oxidation mechanism. We found that bi-CoPc on a carbon support (bi-CoPc/carbon) shows an overpotential of 357 mV at 10 mA cm-2, much lower than that of mono-CoPc/carbon (>450 mV). Kinetic analysis reveals that the rate-determining step (RDS) of the oxygen evolution reaction (OER) over both electrocatalysts is a nucleophilic attack process involving a hydroxy anion (OH-). However, the substrate nucleophilically attacked by OH- for bi-CoPc is the phthalocyanine cation-radical species (CoII-Pc-Pc˙+-CoII-OH) that is formed from the oxidation of the phthalocyanine ring, while cobalt oxidized species (Pc-CoIII-OH) is involved in mono-CoPc as evidenced by the operando UV-vis spectroelectrochemistry technique. DFT calculations show that the reaction barrier for the nucleophilic attack of OH- on CoII-Pc-Pc˙+-CoII-OH is 1.67 eV, lower than that of mono-CoPc with Pc-CoIII-OH nucleophilically attacked by OH- (1.78 eV). The good agreement between the experimental and theoretical results suggests that bi-CoPc can effectively stabilize the accumulated oxidative charges in the phthalocyanine ring, and is thus bestowed with a higher OER performance.

9.
Aquat Toxicol ; 249: 106211, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35667248

RESUMO

4-octylphenol (4-OP), a toxic estrogenic environmental pollutant, can threaten aquatic animal and human health. However, toxic effect of 4-OP on fish has not been reported. To investigate molecular mechanism of gill poisoning caused by 4-OP exposure, a carp 4-OP poisoning model was established, and then blood and gills were collected on day 60. The results demonstrated that gill was a target organ attacked by 4-OP, and exposure to 4-OP caused carp gill inflammatory injury. There were 1605 differentially expressed genes (DEGs, including 898 up-regulated DEGs and 707 down-regulated DEGs). KEGG and GO were used to further analyze obtained 1605 DEGs, indicating that complement activation, immune response, and inflammatory response participated in the mechanism of 4-OP-caused carp gill inflammatory injury. Our data at transcription level further revealed that 4-OP caused complement activation through triggering complement component 3a/complement component 3a receptor (C3a/C3aR) axis and complement component 5a/complement component 5a receptor 1 (C5a/C5aR1) axis, induced immunosuppression through the imbalances of T helper (Th) 1/Th2 cells and regulatory T (Treg)/Th17 cells, as well as caused inflammatory injury via toll like receptor 7/inhibitor kappa B alpha/nuclear factor-kappa B (TLR7/IκBα/NF-κB) pathway. Taken together, immunosuppression participated in complement activation-mediated inflammatory damage in carp gills after 4-OP treatment. The findings of this study will provide pioneering information and theoretical support for the mechanism of 4-OP poisoning, and will provide reference for the assessment of estrogenic environmental pollution risk.


Assuntos
Carpas , Ativação do Complemento , Fenóis , Poluentes Químicos da Água , Animais , Carpas/metabolismo , Complemento C3a/metabolismo , Complemento C5a/metabolismo , Proteínas de Peixes/genética , Brânquias/metabolismo , Terapia de Imunossupressão , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Fenóis/toxicidade , Receptor 7 Toll-Like/metabolismo , Poluentes Químicos da Água/toxicidade
10.
Adv Mater ; 34(29): e2110610, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35589018

RESUMO

Photoelectrochemical (PEC) water splitting for renewable hydrogen production has been regarded as a promising solution to utilize solar energy. However, most photoelectrodes still suffer from poor film quality and poor charge separation properties, mainly owing to the possible formation of detrimental defects including microcracks and grain boundaries. Herein, a molecular coordination engineering strategy is developed by employing acetylacetone (Acac) and poly(ethylene glycol) (PEG) dual ligands to regulate the nucleation and crystal growth of the lead chromate (PbCrO4 ) photoanode, resulting in the formation of a high-quality film with large grain size, well-stitched grain boundaries, and reduced oxygen vacancies defects. With these efforts, the nonradiative charge recombination is efficiently suppressed, leading to the enhancement of its charge separation efficiency from 47% to 90%. After decorating with Co-Pi cocatalyst, the PbCrO4 photoanode achieves a photocurrent density of 3.15 mA cm-2 at 1.23 V (vs RHE under simulated AM1.5G) and an applied bias photon-to-current efficiency (ABPE) of 0.82%. This work provides a new strategy to modulate the nucleation and growth of high-quality photoelectrodes for efficient PEC water splitting.

11.
Animals (Basel) ; 12(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35158719

RESUMO

This study aims to identify molecular marker loci that could be applied in broiler breeding programs. In this study, we used public databases to locate the Transcription factor 21 (TCF21) gene that affected the economically important traits in broilers. Ten single nucleotide polymorphisms were detected in the TCF21 gene by monoclonal sequencing. The polymorphisms of these 10 SNPs in the TCF21 gene were significantly associated (p < 0.05) with multiple growth and body composition traits. Furthermore, the TT genotype of g.-911T>G was identified to significantly increase the heart weight trait without affecting the negative traits, such as abdominal fat and reproduction by multiple methods. Thus, it was speculated that the g.-911T>G identified in the TCF21 gene might be used in marker-assisted selection in the broiler breeding program.

12.
J Anim Breed Genet ; 139(4): 434-446, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35225379

RESUMO

Chicken internal organs are indispensable parts of the body, but their genetic architectures have not been commonly understood. Herein, we estimated the genetic parameters for heart weight (HW), liver weight (LW), spleen weight (SpW), testis weight (TW), glandular stomach weight (GSW), muscular stomach weight (MSW) and identified single nucleotide polymorphisms (SNPs) and potential candidate genes associated with internal organ weights in an F2 population constructed by crossing broiler cocks derived from Arbor Acres with high abdominal fat content and Baier layer dams (a Chinese native breed). The restricted maximum likelihood (REML) method was applied for genetic parameters estimation of internal organ weights using GCTA software. The results showed that heritabilities of internal organ traits ranged from 0.336 to 0.673 and most of the genetic and phenotypic correlations amongst internal organs weights were positive. A genome-wide association study (GWAS) was performed based on a mixed linear model (MLM) in GEMMA software. Genotypic data were produced from the whole genome re-sequenced (26 F0 individuals were re-sequenced at 10 × coverage; 519 F2 individuals were re-sequenced at 3 × coverage). A total of 7,890,258 SNPs remained to be analysed after quality control and genotype imputation. The GWAS results indicated that significant SNPs responsible for internal organ traits were scattered on the different chicken chromosomes 1-5, 8, 11, 14, 16, 18, 19 and 27. Amongst the annotated genes, fibronectin type III domain containing 3A (FNDC3A), LOC101748122, membrane palmitoylated protein 6 (MPP6), LOC107049584 and KAT8 regulatory NSL complex subunit 1 (KANSL1) were the most promising candidates for internal organ traits. The findings will provide instrumental information for understanding the genetic basis of internal organ development.


Assuntos
Galinhas , Estudo de Associação Genômica Ampla , Animais , Galinhas/genética , Estudo de Associação Genômica Ampla/veterinária , Genótipo , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único
13.
Angew Chem Int Ed Engl ; 61(13): e202117809, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35043530

RESUMO

Herein, we report a series of CuPd catalysts for electrochemical hydrogenation (ECH) of furfural to 2-methylfuran (MF or FurCH3 where Fur=furyl) in aqueous 0.1 M acetic acid (pH 2.9). The highest faradaic efficiency (FE) for MF reached 75 % at -0.58 V vs. reversible hydrogen electrode with an average partial current density of 4.5 mA cm-2 . In situ surface-enhanced Raman spectroscopic and kinetic isotopic experiments suggested that electrogenerated adsorbed hydrogen (Hads ) was involved in the reaction and incorporation of Pd enhanced the surface coverage of Hads and optimized the adsorption pattern of furfural, leading to a higher FE for MF. Density functional theory calculations revealed that Pd incorporation reduced the energy barrier for the hydrogenation of FurCH2 * to FurCH3 *. Our study demonstrates that catalyst surface structure/composition plays a crucial role in determining the selectivity in ECH and provides a new strategy for designing advanced catalysts for ECH of bio-derived oxygenates.

14.
BMC Genom Data ; 23(1): 1, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979907

RESUMO

BACKGROUND: The identification of markers and genes for growth traits may not only benefit for marker assist selection /genomic selection but also provide important information for understanding the genetic foundation of growth traits in broilers. RESULTS: In the current study, we estimated the genetic parameters of eight growth traits in broilers and carried out the genome-wide association studies for these growth traits. A total of 113 QTNs discovered by multiple methods together, and some genes, including ACTA1, IGF2BP1, TAPT1, LDB2, PRKCA, TGFBR2, GLI3, SLC16A7, INHBA, BAMBI, APCDD1, GPR39, and GATA4, were identified as important candidate genes for rapid growth in broilers. CONCLUSIONS: The results of this study will provide important information for understanding the genetic foundation of growth traits in broilers.


Assuntos
Galinhas , Estudo de Associação Genômica Ampla , Animais , Galinhas/genética , Genômica , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
15.
Biochem Biophys Res Commun ; 587: 131-138, 2022 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-34872001

RESUMO

BACKGROUND/AIM: Previously, we showed that transcription factor 21 (TCF21) promotes chicken preadipocyte differentiation. However, the genome-wide TCF21 binding sites and its downstream target genes in chicken adipogenesis were unknown. METHODS: ChIP-Seq and RNA-Seq were used to screen candidate targets of TCF21. qPCR and luciferase reporter assay were applied to verify the sequencing results. Western blotting, oil red-O staining and pharmacological treatments were performed to investigate the function of 5-hydroxytryptamine receptor 2A (HTR2A), one of the bonafide direct downstream binding targets of TCF21. RESULTS: A total of 94 candidate target genes of TCF21 were identified. ChIP-qPCR, RT-qPCR, and luciferase reporter assay demonstrated that HTR2A is one of the bonafide direct downstream binding targets of TCF21. HTR2A expression in adipose tissue was upregulated in fat line broilers. Also, the abundance of HTR2A gradually increased during the adipogenesis process. Interestingly, pharmacological enhancement or inhibition of HTR2A promoted or attenuated the differentiation of preadipocytes, respectively. Furthermore, HTR2A inhibition impaired the TCF21 promoted adipogenesis. CONCLUSIONS: We profiled the genome-wide TCF21 binding sites in chicken differentiated preadipocytes revealing HTR2A as the direct downstream target of TCF21 in adipogenesis.


Assuntos
Adipócitos/metabolismo , Adipogenia/genética , Proteínas Aviárias/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Galinhas/genética , Genoma , Receptor 5-HT2A de Serotonina/genética , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Anfetaminas/farmacologia , Animais , Proteínas Aviárias/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Transformada , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Ketanserina/farmacologia , Luciferases/genética , Luciferases/metabolismo , Masculino , Ligação Proteica , Receptor 5-HT2A de Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Transdução de Sinais
16.
Bioresour Bioprocess ; 9(1): 73, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38647607

RESUMO

BACKGROUND: The combination of metal-catalyzed reactions and enzyme catalysis has been an essential tool for synthesizing chiral pharmaceutical intermediates in the field of drug synthesis. Metal catalysis commonly enables the highly efficient synthesis of molecular scaffolds under harsh organic conditions, whereas enzymes usually catalyze reactions in mild aqueous medium to obtain high selectivity. Since the incompatibility between metal and enzyme catalysis, there are limitations on the compatibility of reaction conditions that must be overcome. FINDINGS: We report a chemoenzymatic cascade reaction involved Palladium (Pd) catalyzed Suzuki-Miyaura coupling and whole-cell catalyzed C = O asymmetric reduction for enantioselective synthesis of value-added chiral alcohol. The cell membrane serves as a natural barrier can protect intracellular enzymes from organic solvents. CONCLUSIONS: With dual advantages of cascade catalysis and biocompatibility, our work provides a rational strategy to harvest chiral alcohols in high yield and excellent enantioselectivity, as a channel to establish chemoenzymatic catalysis.

17.
Genes (Basel) ; 12(12)2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34946919

RESUMO

The molecular mechanisms of transcription factor 21 (TCF21) in regulating chicken adipogenesis remain unclear. Thus, the current study was designed to investigate the signaling pathway mediating the effect of TCF21 on chicken adipogenesis. Immortalized chicken preadipocytes cell line (ICP), a preadipocyte cell line stably overexpressing TCF21 (LV-TCF21) and a control preadipocyte cell line (LV-control) were used in the current study. We found that the phosphorylation of c-Jun N-terminal kinases (JNK) was significantly elevated in LV-TCF21 compared to LV-control. After treating ICP cells with a JNK inhibitor SP600125, the differentiation of ICP was inhibited, as evidenced by decreased accumulation of lipid droplets and reduced expression of peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding protein α (C/EBPα), adipocyte fatty acid binding protein (A-FABP), and lipoprotein lipase (LPL). Moreover, we found that the inhibition of JNK by SP600125 remarkably impaired the ability of TCF21 to drive adipogenesis. Taken together, our results suggest that TCF21 promotes the differentiation of adipocytes at least in part via activating MAPK/JNK pathway.


Assuntos
Adipócitos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular/fisiologia , Galinhas/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Transdução de Sinais/fisiologia , Adipogenia/fisiologia , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Células Cultivadas , Proteínas de Ligação a Ácido Graxo/metabolismo , Metabolismo dos Lipídeos/fisiologia , PPAR gama/metabolismo , Fosforilação/fisiologia
18.
Phys Rev E ; 104(5-2): 055103, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34942694

RESUMO

A theoretical derivation of slip boundary conditions for single-species gas and binary gas mixture based on two typical gas-surface scattering kernels is presented. If the Maxwell model is assumed, then the derived slip boundary conditions are consistent with the previous conclusions. Considering the limitation of the Maxwell model in describing the complexity of gas-surface scattering behavior, we further perform theoretical analyses based on the Cercignani-Lampis-Lord (CLL) model, where separate accommodation coefficients in the tangential and normal directions are defined. Our results demonstrate that for both single-species gas and binary gas mixture, the velocity slip predicted by the CLL model is only dependent on the tangential accommodation coefficient, while the temperature jump determined by the CLL model is related to the accommodation coefficients in both tangential and normal directions. To account for the collision effect in the Knudsen layer, we propose to add correction terms to the theoretical models, and the corrected slip coefficients agree well with the previous numerical results obtained by solving Boltzmann equation for single-species gas. Moreover, the slip boundary conditions for binary gas mixture based on the CLL model are determined theoretically for the first time. Since at most situations the tangential and normal accommodation coefficients are not equal, the temperature jump boundary condition based on the CLL model is expected to give more accurate predictions about temperature distribution and heat flux at the boundaries, particularly for hypersonic gas flows with strong nonequilibrium effect.

19.
Science ; 373(6554): 547-555, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34326237

RESUMO

RNA polymerase I (Pol I) transcription takes place at the border of the fibrillar center (FC) and the dense fibrillar component (DFC) in the nucleolus. Here, we report that individual spherical FC/DFC units are coated by the DEAD-box RNA helicase DDX21 in human cells. The long noncoding RNA (lncRNA) SLERT binds to DDX21 RecA domains to promote DDX21 to adopt a closed conformation at a substoichiometric ratio through a molecular chaperone-like mechanism resulting in the formation of hypomultimerized and loose DDX21 clusters that coat DFCs, which is required for proper FC/DFC liquidity and Pol I processivity. Our results suggest that SLERT is an RNA regulator that controls the biophysical properties of FC/DFCs and thus ribosomal RNA production.


Assuntos
Nucléolo Celular/metabolismo , RNA Helicases DEAD-box/metabolismo , RNA Polimerase I/metabolismo , RNA Longo não Codificante/metabolismo , Linhagem Celular , RNA Helicases DEAD-box/química , DNA Ribossômico/metabolismo , Humanos , Chaperonas Moleculares/metabolismo , Conformação Proteica , Domínios Proteicos , Multimerização Proteica , Transcrição Gênica
20.
RNA ; 27(6): 725-733, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33846273

RESUMO

The mammalian cell nucleus contains different types of membrane-less nuclear bodies (NBs) consisting of proteins and RNAs. Microscopic imaging has been widely applied to study the organization and structure of NBs. However, current fixation methods are not optimized for such imaging: When a fixation method is chosen to maximize the quality of the RNA fluorescence in situ hybridization (FISH), it often limits the labeling efficiency of proteins or affects the ultrastructure of NBs. Here, we report that addition of glyoxal (GO) into the classical paraformaldehyde (PFA) fixation step not only improves FISH signals for RNAs in NBs via augmented permeability of the fixed nucleus and enhanced accessibility of probes, but also largely preserves protein fluorescent signals during fixation and immunostaining. We also show that GO/PFA fixation enables the covisualization of different types of nuclear bodies with minimal impact on their ultrastructures under super-resolution microscopy.


Assuntos
Estruturas do Núcleo Celular/ultraestrutura , Fixadores/química , Formaldeído/química , Glioxal/química , Hibridização in Situ Fluorescente/métodos , Polímeros/química , Células HEK293 , Células HeLa , Humanos
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