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Multiple intracellular microRNA (miRNA) detection is essential for disease diagnosis and management. Nonetheless, the real-time detection of multiple intracellular miRNAs has remained challenging. Herein, we have developed an ultrasound (US)-powered nanomotor-based dynamic fluorescent probe for the real-time OFF-ON fluorescent determination of multiple intracellular miRNAs. The new probe relies on the utilization of multicolored quantum dot (QD)-labeled single-stranded DNA (ssDNA)/graphene oxide (GO)-coated US-powered gold nanowire (AuNW) nanomotors. The fluorescence of QDs is quenched due to π-π interactions with the GO. Upon binding to target miRNAs, the QDs-ssDNA is now distant from the AuNWs, resulting in effective OFF-ON QD fluorescence switching. Compared with conventional passive probes, the dynamic fluorescent probe enhances probe-target interactions by using the US-propelled nanomotor, resulting in exceptionally efficient and prompt hybridization. Simultaneous quantitative analysis of miR-10b and miR-21 in vitro can be achieved within 15 min with high sensitivity and specificity. Additionally, multicolor QDs provide strong signal intensity and multiplexed detection, enabling one-step real-time discrimination between cancer cells (A549) and normal cells (L02). The obtained results are in good agreement with those from qRT-PCR. This dynamic fluorescent probe based on a nanomotor and QDs enables rapid "on the move" specific detection of multiple intracellular miRNAs in intact cells, facilitating real-time monitoring of diverse intracellular miRNA expression, and it could pave the way for novel applications of nanomotors in biodetection.
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Corantes Fluorescentes , Grafite , MicroRNAs , Pontos Quânticos , MicroRNAs/análise , Humanos , Corantes Fluorescentes/química , Pontos Quânticos/química , Grafite/química , Ouro/química , DNA de Cadeia Simples/química , Nanofios/química , Ondas Ultrassônicas , Células A549RESUMO
According to the latest cancer research data, there are a significant number of new cancer cases and a substantial mortality rate each year. Although a substantial number of clinical patients are treated with existing cancer drugs each year, the efficacy is unsatisfactory. The incidence is still high and the effectiveness of most cancer drugs remains unsatisfactory. Therefore, we evaluated the human proteins for their causal relationship to for cancer risk and therefore also their potential as drug targets. We used summary tumors data from the FinnGen and cis protein quantitative trait loci (cis-pQTL) data from a genome-wide association study, and employed Mendelian randomization (MR) to explore the association between potential drug targets and nine tumors, including breast, colorectal, lung, liver, bladder, prostate, kidney, head and neck, pancreatic caners. Furthermore, we conducted MR analysis on external cohort. Moreover, Bidirectional MR, Steiger filtering, and colocalization were employed to validate the main results. The DrugBank database was used to discover potential drugs of tumors. Under the threshold of False discovery rate (FDR) < 0.05, results showed that S100A16 was protective protein and S100A14 was risk protein for human epidermal growth factor receptor 2-positive (HER-positive) breast cancer, phosphodiesterase 5A (PDE5A) was risk protein for colorectal cancer, and melanoma inhibitory activity (MIA) was protective protein for non-small cell lung carcinoma (NSCLC). And there was no reverse causal association between them. Colocalization analysis showed that S100A14 (PP.H4.abf = 0.920) and S100A16 (PP.H4.abf = 0.932) shared causal variation with HER-positive breast cancer, and PDE5A (PP.H4.abf = 0.857) shared causal variation with colorectal cancer (CRC). The MR results of all pQTL of PDE5A and MIA were consistent with main results. In addition, the MR results of MIA and external outcome cohort were consistent with main results. In this study, genetic predictions indicate that circulating S100 calcium binding protein A14 (S100A14) and S100 calcium binding protein A16 (S100A16) are associated with increase and decrease in the risk of HER-positive breast cancer, respectively. Circulating PDE5A is associated with increased risk of CRC, while circulating MIA is associated with decreased risk of NSCLC. These findings suggest that four proteins may serve as biomarkers for cancer prevention and as potential drug targets that could be expected for approval.
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Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Neoplasias , Humanos , Neoplasias/genética , Locos de Características Quantitativas , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Polimorfismo de Nucleotídeo Único , Predisposição Genética para DoençaRESUMO
The small size of the Cas nuclease fused with various effector domains enables a broad range of function. Although there are several ways of reducing the size of the Cas nuclease complex, no efficient or generalizable method has been demonstrated to achieve protein miniaturization. In this study, we establish an Interaction, Dynamics and Conservation (IDC) strategy for protein miniaturization and generate five compact variants of Cas13 with full RNA binding and cleavage activity comparable the wild-type enzymes based on a combination of IDC strategy and AlphaFold2. In addition, we construct an RNA base editor, mini-Vx, and a single AAV (adeno-associated virus) carrying a mini-RfxCas13d and crRNA expression cassette, which individually shows efficient conversion rate and RNA-knockdown activity. In summary, these findings highlight a feasible strategy for generating downsized CRISPR/Cas13 systems based on structure predicted by AlphaFold2, enabling targeted degradation of RNAs and RNA editing for basic research and therapeutic applications.
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Dependovirus , Endonucleases , Miniaturização , RNA , Edição de RNARESUMO
BACKGROUND: Adenine base editors (ABEs) are promising therapeutic gene editing tools that can efficiently convert targeted Aâ¢T to Gâ¢C base pairs in the genome. However, the large size of commonly used ABEs based on SpCas9 hinders its delivery in vivo using certain vectors such as adeno-associated virus (AAV) during preclinical applications. Despite a number of approaches having previously been attempted to overcome that challenge, including split Cas9-derived and numerous domain-deleted versions of editors, whether base editor (BE) and prime editor (PE) systems can also allow deletion of those domains remains to be proven. In this study, we present a new small ABE (sABE) with significantly reduced size. RESULTS: We discovered that ABE8e can tolerate large single deletions in the REC2 (Δ174-296) and HNH (Δ786-855) domains of SpCas9, and these deletions can be stacked together to create a new sABE. The sABE showed higher precision than the original ABE8e, with proximally shifted protospacer adjacent motif (PAM) editing windows (A3- A15), and comparable editing efficiencies to 8e-SaCas9-KKH. The sABE system efficiently generated A-G mutations at disease-relevant loci (T1214C in GAA and A494G in MFN2) in HEK293T cells and several canonical Pcsk9 splice sites in N2a cells. Moreover, the sABE enabled in vivo delivery in a single adeno-associated virus (AAV) vector with slight efficiency. Furthermore, we also successfully edited the genome of mouse embryos by microinjecting mRNA and sgRNA of sABE system into zygotes. CONCLUSIONS: We have developed a substantially smaller sABE system that expands the targeting scope and offers higher precision of genome editing. Our findings suggest that the sABE system holds great therapeutic potential in preclinical applications.
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Edição de Genes , Pró-Proteína Convertase 9 , RNA Guia de Sistemas CRISPR-Cas , Animais , Humanos , Camundongos , Adenina , Células HEK293RESUMO
Many therapeutic applications of CRISPR-Cas9 gene editing rely on delivery using the highly versatile adeno-associated virus (AAV) vector. The smallest type II Cas9 ortholog-Cje1Cas9, derived from Campylobacter jejuni with <1,000 amino acids-is particularly attractive for AAV delivery. However, the complex protospacer adjacent motif (PAM) of Cje1Cas9 (N3VRYAC) greatly restricts the density of recognition sequences in human genome. In this study, we identify two compact CjeCas9 orthologs designated as Cje2Cas9 and Cje3Cas9, whose PAM-interacting residues are different from those of the well-known Cje1Cas9. They can induce efficient genome editing in human cells, and their simpler trinucleotide PAM (N4CYA) requirements expand the scope of targeting. Moreover, Cje3Cas9 efficiently disrupts the Tyr gene in mice after being micro-injected into zygotes with the corresponding sgRNA. It also successfully disrupts the Pcsk9 gene in 8-week-old mouse liver after delivery with an sgRNA using an all-in-one AAV delivery vehicle. The gene-edited mice showed lower cholesterol level than wild-type mice. Notably, the 8e-nCje3-ABE and an sgRNA targeting Pcsk9 were successfully packaged into a single AAV vector for genome editing in adult mouse liver, with editing efficiency up to 12%. Thus, simple PAMs and a compact size enable Cje2/3Cas9 to expand the target scope of CRISPR-Cas9 toolsets, exhibiting considerable potential for therapeutic applications.
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Edição de Genes , Pró-Proteína Convertase 9 , Adenina , Animais , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Camundongos , Pró-Proteína Convertase 9/genéticaRESUMO
Epigenetic alteration is a pivotal factor in tumor metastasis. PHD finger protein 13 (PHF13) is a recently identified epigenetic reader of H3K4me2/3 that functions as a transcriptional co-regulator. In this study, we demonstrate that PHF13 is required for pancreatic-cancer-cell growth and metastasis. Integrative analysis of transcriptome and epigenetic profiles provide further mechanistic insights into the epigenetic regulation of genes associated with cell metastasis during the epithelial-to-mesenchymal transition (EMT) induced by transforming growth factor ß (TGFß). Our data suggest PHF13 depletion impairs activation of TGFß stimulated genes and correlates with a loss of active epigenetic marks (H3K4me3 and H3K27ac) at these genomic regions. These observations argue for a dependency of TGFß target activation on PHF13. Furthermore, PHF13-dependent chromatin regions are enriched in broad H3K4me3 domains and super-enhancers, which control genes critical to cancer-cell migration and invasion, such as SNAI1 and SOX9. Overall, our data indicate a functional and mechanistic correlation between PHF13 and EMT.
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Proteínas de Ligação a DNA , Epigênese Genética , Transição Epitelial-Mesenquimal , Neoplasias , Fatores de Transcrição , Linhagem Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , Proteínas de Ligação a DNA/genética , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/genética , Humanos , Neoplasias/patologia , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta/metabolismoRESUMO
CRISPR/Cas9 system is a robust genome editing platform in biotechnology and medicine. However, it generally produces small insertions/deletions (indels, typically 1-3 bp) but rarely induces larger deletions in specific target sites. Here, we report a cytidine deaminase-Cas9 fusion-induced deletion system (C-DEL) and an adenine deaminase-Cas9 fusion-induced deletion system (A-DEL) by combining Cas9 with rat APOBEC1 (rA1) and TadA 8e, respectively. Both C-DEL and A-DEL improve the efficiency of deletions compared with the conventional Cas9 system in human cells. In addition, the C-DEL system generates a considerable fraction of predictable multinucleotide deletions from 5'-deaminated C bases to the Cas9-cleavage site and increases the proportion of larger deletions at the target loci. Taken together, the C-DEL and A-DEL systems provide a practical strategy for producing efficient multinucleotide deletions, expanding the CRISPR/Cas9 toolsets for gene modifications in human cells.
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Sistemas CRISPR-Cas , Edição de Genes , Humanos , Ratos , Animais , Sistemas CRISPR-Cas/genética , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Mutação INDEL/genética , Desaminase APOBEC-1/genéticaRESUMO
Compact CRISPR-Cas9 systems that can be packaged into an adeno-associated virus (AAV) show promise for gene therapy. However, the requirement of protospacer adjacent motifs (PAMs) restricts the target scope. To expand this repertoire, we revisited and optimized a small Cas9 ortholog derived from Streptococcus pasteurianus (SpaCas9) for efficient genome editing in vivo. We found that SpaCas9 enables potent targeting of 5'-NNGYRA-3' PAMs, which are distinct from those recognized by currently used small Cas9s; the Spa-cytosine base editor (CBE) and Spa-adenine base editor (ABE) systems efficiently generated robust C-to-T and A-to-G conversions both in vitro and in vivo. In addition, by exploiting natural variation in the PAM-interacting domain, we engineered three SpaCas9 variants to further expand the targeting scope of compact Cas9 systems. Moreover, mutant mice with efficient disruption of the Tyr gene were successfully generated by microinjection of SpaCas9 mRNA and the corresponding single guide RNA (sgRNA) into zygotes. Notably, all-in-one AAV delivery of SpaCas9 targeting the Pcsk9 gene in adult mouse liver produced efficient genome-editing events and reduced its serum cholesterol. Thus, with distinct PAMs and a small size, SpaCas9 will broaden the CRISPR-Cas9 toolsets for efficient gene modifications and therapeutic applications.
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Edição de Genes , Pró-Proteína Convertase 9 , Animais , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas , Camundongos , Pró-Proteína Convertase 9/genética , RNA Guia de Cinetoplastídeos/genética , StreptococcusRESUMO
Cucurbitacin B (CuB), a natural product, has anti-tumor effects on various cancers. In order to investigate the expression of long non-coding RNAs (lncRNA), we carried out RNA sequencing (RNA-seq) and quantitative PCR (qPCR). The data indicated that CAL27 and SCC9 tongue squamous cell carcinoma (TSCC) cells had reduced expression of X-inactive specific transcript (XIST) after CuB treatment. Moreover, our results showed increased expression of XIST in human tongue cancer. In this study, CuB treatment inhibited proliferation, migration and invasion of SCC9 cells, and induced cellular apoptosis. Interestingly, knockdown of XIST led to inhibition of cell proliferation and induced apoptosis in vitro. In addition, reduced expression of XIST suppressed cell migration and invasion. MicroRNA 29b (miR-29b) was identified as a direct target of XIST. Previous reports indicated that miR-29b regulates p53 protein. Our results suggest that increased expression of miR-29b induces cell apoptosis through p53 protein. The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (CRISPR/Cas9) system validated the role of XIST knockout in tumor development in vivo. Together, these results suggest that CuB exerts significant anti-cancer activity by regulating expression of XIST via miR-29b.
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Owing to their unique afterglow ability, long-wavelength light activatable persistent luminescence (PersL) nanoparticles (PLNPs) have been emerging as an important category of imaging probes. Long-wavelength LED light has been shown to be effective in recharging these nanoparticles. However, finding a simple and effective method to amplify such renewable PersL signals under long-wavelength light is still a key challenge. Herein, we discovered that a dye-sensitization strategy was able to effectively boost the renewable PersL signals of the NIR emitting ZnGa2 O4 :Cr3+ (ZGC)) under long-wavelength LED light. Moreover, as a proof-of-principle tumorectomy demonstration, this new class of dye sensitized ZGC enabled simultaneous intraoperative anatomic tumor navigation and effective microscopic detection of tumor cells in pathological diagnosis.
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Previous studies have revealed the critical roles of the N6-methyladenosine (m6A) modification of long non-coding RNAs (lncRNAs) in cancers, but the relationship between the oncogenic role of the lncRNA THOR (a representative of cancer/testis lncRNAs) and m6A modification remains unclear. Here, we show that the internal m6A modification of the lncRNA THOR via an m6A-reader-dependent modality regulates the proliferation of cancer cells. Our findings demonstrated that the loss of the lncRNA THOR inhibits the proliferation, migration, and invasion of cancer cells in vitro and in vivo. In addition, m6A is highly enriched on lncRNA THOR transcripts, which contain GA (m6A) CA, GG (m6A) CU, and UG (m6A) CU sequence motifs. RIP-qRT-PCR and RNA pull-down assay results revealed that the specific m6A readers YTHDF1 and YTHDF2 can read the m6A motifs and regulate the stability of the lncRNA THOR (stabilization and decay). These m6A-dependent RNA-protein interactions can maintain the oncogenic role of the lncRNA THOR. Collectively, these findings highlight the critical role of the m6A modification in oncogenic lncRNA THOR and reveal a novel long non-coding RNA regulatory mechanism, providing a new way to explore RNA epigenetic regulatory patterns in the future.
Assuntos
Adenosina/análogos & derivados , Linhagem da Célula/genética , RNA Longo não Codificante/metabolismo , Adenosina/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Humanos , Camundongos Nus , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/metabolismo , Transcrição GênicaRESUMO
Microplastic (MP) pollution has become an area of increasing concern because MPs accumulate various types of pollutants. Many previous studies have explored the interactions between MPs and hydrophobic pollutants. However, little research has been conducted on hydrophilic pollutants, which are of much higher concentration and ubiquitous in environment. Surfactants cause hydrophobic MPs to become hydrophilic, which may significantly enhance their capacities to adsorb hydrophilic pollutants. This study explored the influence of co-existing surfactants on the adsorption of ionic organic pollutants by MPs, and found that the presence of an ionic surfactant could significantly enhance the capacity of polyvinyl chloride (PVC, 0.2 mm) MPs to adsorb pollutants with opposite charges. The Langmuir methylene blue adsorption capacity of PVC could be increased from 172 to 4417 ppm in the presence of a sodium dodecyl benzene sulfonate surfactant. Nonionic surfactants impeded the adsorption of both cationic and anionic pollutants due to the steric resistance of the hydrophilic polyethelene glycol chains. The electrostatic interaction mechanism dominated the interfacial behaviors of ionic pollutants on surfactant-adsorbed MP interfaces. The effects of the surfactants were further verified using four different model pollutants and six surfactants. The adsorption capacities of real environmental MPs, including PVC, polyethylene (PE), polypropylene (PP), and polystyrene (PS), increased by three to twenty-six times. The adsorption properties of MPs may be determined by the presence of co-existing surfactants, rather than their polymer species or additives.
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Poluentes Ambientais , Poluentes Químicos da Água , Adsorção , Microplásticos , Plásticos , TensoativosRESUMO
The previous report shows the minimal promoter (P1) contributes to the Xist RNA activation in cells, while the role of the Xist P1 has not yet been investigated in animal individuals. Here, female Xist P1 knockout rabbits (Xist P1-/-) were generated for the studies. The results showed that there is no significant difference in transmission ratio, Xist and X-linked genes expression, and Xist RNA localization between the female wild type (WT) and Xist P1-/- rabbits, suggesting that P1 is non-essential for Xist expression and XCI in rabbits. Our study has explored the function of Xist P1 in animal level for the first time, and the results provide new ideas for future studies of XCI mechanisms.
Assuntos
Genes Ligados ao Cromossomo X , Regiões Promotoras Genéticas , RNA Longo não Codificante/genética , Inativação do Cromossomo X , Animais , Biópsia , Sistemas CRISPR-Cas , Análise Mutacional de DNA , Feminino , Técnicas de Inativação de Genes , Imuno-Histoquímica , Camundongos Transgênicos , CoelhosRESUMO
BACKGROUND: Increasing studies have shown that application of pulmonary rehabilitation may improve the quality of life of chronic obstructive pulmonary disease (COPD) patients. However, the results of some studies still remained controversial and sample size of them limited to small number of participants. A systematic review and meta-analysis was designed to evaluate the efficacy of pulmonary rehabilitation for improving the quality of life in patients with COPD. METHODS: We searched the Cochrane Library, PubMed, EMBASE and Web of Science up to March 29, 2019 to identify relevant randomized controlled trials (RCTs) analyzing and evaluating the efficacy of pulmonary rehabilitation (PR) in patients with COPD. Participants were randomly assigned to receive PR (intervention group) or usual care (controller group). We used St. George's Respiratory Questionnaire (SGRQ) scores as evaluating indicators of quality of life. Mean differences (MDs) with 95% confidence intervals (CIs) were estimated to compare the outcomes of the groups. We also performed subgroup analysis for the pooled results of pulmonary rehabilitation effects in COPD patients. Besides, sensitivity analysis was performed to examine the stability of the combined results. Two reviewers assessed trial quality and extracted data independently. All statistical analyses were performed using standard statistical procedures provided in Review Manager 5.2 and Stata 12.0. RESULTS: Nineteen randomized controlled trials (N = 1146 participants) were identified for the present analysis. Comparing pulmonary rehabilitation groups with usual care groups (control groups), statistically significant improvements were noted in total score of SGRQ, with MD of -6.53. In addition, life quality improvement of SGRQ scores was better than 5 units in symptoms score, impacts score and activity score, with MDs of -5.01, -7.23 and -6.08, respectively. CONCLUSIONS: Rehabilitation may constitute one of important components of the management of COPD and may be beneficial in improving the quality of life. Future research should focus on identifying which components of pulmonary rehabilitation are essential, its ideal length and location, the degree of supervision and intensity of training required and how long treatment effects persist.
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Doença Pulmonar Obstrutiva Crônica/reabilitação , Qualidade de Vida , Terapia Respiratória/psicologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Terapia Respiratória/métodos , Resultado do TratamentoRESUMO
Excess natural organic matter (NOM) in water not only lead to unpleasant black color and dissolved oxygen depletion in wastewater and natural water body but also causes carcinogenic chlorinated organic byproduct during drinking water chlorine disinfection. We try to develop a novel cost-effective and green technology for water NOM removal. In our simulated NOM removal process using humic acid (HA) as typical organic matter, we find that mesoporous nano-MgO performs an abnormally high NOM removal capacity (1260â¯mg-HA/g-MgO, or 446 mgC/g-MgO) when coupled with microfiltration membrane separation, which can't be illustrated by traditional adsorption mechanism. Actually, Mg2+ from dissolved Mg(OH)2 contributesâ¯â¼â¯92% NOM removal via coagulation while Mg(OH)2 is responsible for the residueâ¯â¼â¯8% via adsorption. MgO serves as a two-in-one coagulant and adsorbent. The MgO treatment process is highly pH sensitive and weak acidic condition is favored for high NOM removal efficiency. MgO can be regenerated for more than 10 circulations by annealing Mg(OH)2/Mg-NOM composite at 500 °C, so that our MgO recycling process will be sustainable without the need of continuous chemical purchase. More importantly, no solid waste is generated in this novel process. This MgO-recycling NOM-removal process is simple, efficient, and sustainable for water NOM removal and will be significant in promoting novel sustainable technologies for NOM- or HA-related water remediation and treatment while minimizing the generation of solid waste.
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FSH plays a key role in the function of the reproductive system of human beings and is widely used both diagnostically and therapeutically in reproductive medicine. With the growing incidence of infertility, the demand for FSH pharmaceutical products is increasing. For this reason, the quality control process for FSH products is becoming more stringent. An accurate determination of bioactivity is crucial for the safety and efficacy of recombinant human follicle stimulating hormone (rhFSH). Up to now, in-vivo bioassay based on FSH-induced increases in rat ovarian weight has been the only method widely accepted by different pharmacopoeias. However this method has such drawbacks as the complex procedures, long assay period and high variability. Here, we established a reporter gene assay (RGA) based on the CHO-K1-FSHR-CRE-Luc cell line that stably expresses human follicle stimulating hormone receptor (hFSHR), as well as a luciferase reporter under the control of cyclic adenosine monophosphate (cAMP) response elements (CRES). Our study showed that our new assay not only has good dose-dependent responsiveness to rhFSH, but it also performs excellently in terms of specificity, precision, linearity, and simplicity compared with in-vivo rat bioassays. These results implied that this robust reporter gene assay may be a viable supplement to the animal in-vivo bioassay and may be employed in potency determination of rhFSH pharmaceutical products.
Assuntos
Bioensaio/métodos , Hormônio Foliculoestimulante Humano/farmacologia , Genes Reporter/genética , Receptores do FSH/metabolismo , Animais , Células CHO , Linhagem Celular , Cricetulus , AMP Cíclico/genética , Estudos de Viabilidade , Luciferases/química , Luciferases/genética , Receptores do FSH/genética , Proteínas Recombinantes/farmacologia , Elementos de Resposta/genéticaRESUMO
Cytidine base editors, which are composed of a cytidine deaminase fused to clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein 9 (Cas9) nickase, enable the efficient conversion of the C·G base pair to T·A in various organisms. However, the currently used rat apolipoprotein B mRNA-editing enzyme, catalytic polypeptide 1(rA1)-based BE3 is often inefficient in target Cs that are immediately downstream of a G (GC context). Here, we observed that, with an 11-nt editing window, an optimized activation-induced cytidine deaminase (AID)-Cas9 fusion can efficiently convert C to T in a variety of sequence contexts in rabbits. Strikingly, the enhanced AID-Cas9 fusion (eAID-BE4max) has significant effectiveness of inducing Tyr p.R299H mutation in GC contexts (from 16.67 to 83.33%) in comparison with BE3 in founder rabbits. Furthermore, the engineered AID-Cas9 variants were produced with reduced bystander activity [eAID (N51G)-BE4max] and increased genome-targeting scope (eAID-NG-BE4max). Overall, this work provides a series of improved tools that were generated using optimized AID-Cas9 fusions and associated engineered variants that can be used for efficient and versatile C-to-T base editing, especially in GC contexts.-Liu, Z., Shan, H., Chen, S., Chen, M., Zhang, Q., Lai, L., Li, Z. Improved base editor for efficient editing in GC contexts in rabbits with an optimized AID-Cas9 fusion.
Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Animais , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Mutação/genética , Reação em Cadeia da Polimerase , Coelhos , Ratos , ZigotoRESUMO
Based on our innovative application of using thick continuous casting slab 0.4C1.5Mn2Cr0.35Mo1.5Ni (high alloy) for the production of high-quality mould steel, the present study investigated the high cracking susceptibility of high-alloy steel and segregation in continuous casting slab. The thermal expansion and the continuous cooling transformation (CCT) curve measurement, together with a high temperature in situ observation, confirmed the martensite phase transition happening at approximately 583 K that would result in an increase in the hardenability and cracking susceptibility. The cracking susceptibility zone was determined by high-temperature mechanical properties measurement. The high-alloy mould steel has no II brittle zone, and III brittle zone is 973-1148 K. As a conclusion, the straightening temperature should be above 1148 K to avoid the cracking during the continuous casting. Moreover, the elemental segregation of carbon, sulfur, chromium, and molybdenum along the cracking was examined by electron probe microanalysis (EPMA) quantitative analysis that might be another reason for the steel crack formation. It shows that Martensite phase transition happened at approximately 583 K that would result in an increase in the hardenability and cracking susceptibility.
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Pure hair and nail ectodermal dysplasia 9 (ECTD-9) is an autosomal recessive genetic disease caused by mutation of HOXC13 and is characterized by hypotrichosis and nail dystrophy in humans. Unlike patients with ECTD-9, Hoxc13-mutated mice and pigs do not faithfully recapitulate the phenotype of hypotrichosis, so there is a limited understanding of the molecular mechanism of Hoxc13-mediated hypotrichosis in animal models and clinically. Here, the homozygous Hoxc13-/- rabbits showed complete loss of hair on the head and dorsum, whereas hypotrichosis in the limbs and tail were determined in the Hoxc13-/- rabbits. In addition, reduced hair follicles (HFs) while the enlarged and increased number of sebaceous glands (SGs) were also found in the Hoxc13-/- rabbits, showing that the disrupted balance between HFs and SGs may respond to hypotrichosis of ECTD-9 in an animal model and clinically. Therefore, our findings demonstrate that Hoxc13-/- rabbits can be used as a model for human ECTD-9, especially to understand the pathologic mechanism of hypotrichosis. Moreover, the disrupted balance between HFs and SGs, especially in the Hoxc13-/- rabbits, can be used as an ideal animal model for dermatology ailments, such as acne and hypotrichosis, in preclinical studies.-Deng, J., Chen, M., Liu, Z., Song, Y., Sui, T., Lai, L., Li, Z. The disrupted balance between hair follicles and sebaceous glands in Hoxc13-ablated rabbits.
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Deleção de Genes , Cabelo/metabolismo , Proteínas de Homeodomínio/genética , Glândulas Sebáceas/metabolismo , Animais , Sistemas CRISPR-Cas , Modelos Animais de Doenças , Displasia Ectodérmica/genética , Hipotricose/congênito , Hipotricose/genética , Mutação , Fenótipo , CoelhosRESUMO
Postoperative neurocognitive disorder (PND) is a major complication in surgical patients, especially the elderly, leading to mild memory impairment after surgery. The underlying pathophysiology remains unknown, although neuroinflammation and blood-brain barrier (BBB) disruption have been increasingly implicated in PND. Emerging evidence suggests that neurokinin-1 receptor (NK-1R), the principal target of proinflammatory neuropeptide substance P (SP), plays a pivotal role in modulating neuroinflammation and BBB integrity. In this study, we used an established mouse model for PND to investigate the effects of a selective NK-1R antagonist L-733,060 on PND-like features after peripheral surgery. Hippocampal SP started to increase at 6 h, peaked at 1 day, and returned to baseline at 3 days after surgery. At 1 day after surgery, NK-1R expression was increased in the hippocampus. At this time point, NK-1R antagonist pretreatment attenuated microgliosis and prevented neutrophil infiltration after surgery. Similarly, proinflammatory cytokines interleukin-1 beta and interleukin-6 were reduced in the hippocampus in NK-1R antagonist-treated mice at 6 h after surgery. Furthermore, surgery-induced BBB disruption, assessed by albumin deposition and expression of tight junction protein claudin-5, was attenuated by NK-1R antagonism at postoperative day 1. Finally, trace fear conditioning test revealed NK-1R antagonism reversed surgery-induced cognitive impairment at 3 days after surgery. Our findings suggest that inhibition of NK-1R signaling protects hippocampus-dependent memory from surgical insult, probably through modulations of neuroinflammation and BBB integrity.