CRISPR-Cas13 is a newly emerging RNA knockdown technology that is comparable to RNAi. Among all members of Cas13, CasRx degrades RNA in human cells with high precision and effectiveness. However, it ...remains unclear whether the efficiency of this technology can be further improved and applied to gene therapy.
In this study, we fuse CasRx crRNA with an antisense ribozyme to construct a synthetic fusion guide RNA that can interact with both CasRx protein and ribozyme and tested the ability of this approach in RNA knockdown and cancer gene therapy. We show that the CasRx-crRNA-ribozyme system (CCRS) is more efficient for RNA knockdown of mRNAs and non-coding RNAs than conventional methods, including CasRx, shRNA, and ribozyme. In particular, CCRS is more effective than wild-type CasRx when targeting multiple transcripts simultaneously. We next use bladder cancer as a model to evaluate the anticancer effects of CCRS targeting multiple genes in vitro and in vivo. CCRS shows a higher anticancer effect than conventional methods, consistent with the gene knockdown results.
Thus, our study demonstrates that CCRS expands the design ideas and RNA knockdown capabilities of Cas13 technology and has the potential to be used in disease treatment.
•The system exhibits half-metallic and semiconductor phases, under different local voltages.•A fully spin polarized transport device is constructed.•High spin polarization is realized without ...external field action.•The magnetic tunneling junction with high tunnel magnetoresistance is constructed by adding local gate voltage.
It is an important topic in spintronics to find regulable half-metallic materials. In this work, by using density functional theory and nonequilibrium Green’s functional method, we find that the van der Waals heterostructures formed by zigzag-edged boron nitride nanoribbons and zigzag-edged graphene nanoribbons (ZGNRs) are spin splitting semiconductors. The energy band gap of the heterostructures can be regulated by applying a local voltage and the semiconductor–metal–semiconductor phase transition can be realized. Two spin-dependent transport devices are constructed based on the heterostructures. One device can generate a fully spin-polarized current within a small bias range, and the other device can generate high spin polarization within a large bias range. Moreover, based on zigzag-edged graphene/boron nitride nanoribbon (ZGBNNR) heterostructures, a dual-probe device with double vertical gates in the electrode regions is designed, which can form a metal–semiconductor–metal tunneling device. These findings indicate that ZGBNNRs can be used in excellent spintronic devices.
To investigate the factors affecting the duration of continuous breastfeeding of infants within 2 years of age, and to explore intervention strategies that may promote breastfeeding duration in ...China.
A self-made electronic questionnaire was used to investigate the breastfeeding duration of infants, and the influencing factors were collected from three levels of individual, family, and social support. The Kruskal-Wallis rank sum test and the multivariable ordinal logistic regression model were used for data analysis. Subgroup analysis was carried out according to region and parity.
A total of 1001 valid samples from 26 provinces across the country were obtained. Among them, 9.9% breastfed for less than 6 months, 38.6% for 6 to 12 months, 31.8% for 12 to 18 months, 6.7% for 18 to 24 months, and 13.1% for more than 24 months. Barriers to sustained breastfeeding included the mother's age at birth being over 31, education level below junior high, cesarean delivery, and the baby's first nipple sucking at 2 to 24 h after birth. Factors that promote continued breastfeeding included freelancer or full-time mother, high breastfeeding knowledge score, supporting breastfeeding, baby with low birth weight, first bottle feeding at 4 months and later, first supplementary food at over 6 months old, high family income, the mother's family and friends supporting breastfeeding, breastfeeding support conditions after returning to work, etc. Conclusion: The breastfeeding duration in China is generally short, and the proportion of mothers breastfeeding until the age of 2 years and above, recommended by WHO, is very low. Multiple factors at the individual, family, and social support levels influence the duration of breastfeeding. It is suggested to improve the current situation by strengthening health education, improving system security, and enhancing social support.
Two-dimensional materials with high-temperature ferromagnetism and half-metallicity have the latest applications in spintronic devices. Based on first-principles calculations, we have investigated a ...novel two-dimensional CrS
2
phase with an orthorhombic lattice. Our results suggest that it is stable in dynamics, thermodynamics, and mechanics. The ground state of monolayer orthorhombic CrS
2
is both ferromagnetic and half-metallic, with a high Curie temperature of 895 K and a large spin-flipping gap on values of 0.804 eV. This room-temperature ferromagnetism and half-metallicity can maintain stability against a strong biaxial strain ranging from −5% to 5%. Meanwhile, increasing strain can significantly maintain the out-of-plane magnetic anisotropy. A density of states analysis, together with the orbital-resolved magnetic anisotropy energy, has revealed that the strain-enhanced MAE is highly related to the 3d-orbital splitting of Cr atoms. Our results suggest the monolayer orthorhombic CrS
2
is an ideal candidate for future spintronics.
Insulin resistance has been regarded as a hallmark of diabetes heart disease (DHD). Numerous studies have shown that insulin resistance can affect blood circulation and myocardium, which indirectly ...cause cardiac hypertrophy and ventricular remodeling, participating in the pathogenesis of DHD. Meanwhile, hyperinsulinemia, hyperglycemia, and hyperlipidemia associated with insulin resistance can directly impair the metabolism and function of the heart. Targeting insulin resistance is a potential therapeutic strategy for the prevention of DHD. Currently, the role of insulin resistance in the pathogenic development of DHD is still under active research, as the pathological roles involved are complex and not yet fully understood, and the related therapeutic approaches are not well developed. In this review, we describe insulin resistance and add recent advances in the major pathological and physiological changes and underlying mechanisms by which insulin resistance leads to myocardial remodeling and dysfunction in the diabetic heart, including exosomal dysfunction, ferroptosis, and epigenetic factors. In addition, we discuss potential therapeutic approaches to improve insulin resistance and accelerate the development of cardiovascular protection drugs.
A key challenge in designing intelligent artificial gene circuits is generating flexible connections between arbitrary components and directly coupling them with endogenous signaling pathways. The ...CRISPR signal conductor based on conditionally inducible artificial transcriptional regulators can link classic cellular protein signals with targeted gene expression, but there are still problems with multiple signal processing and gene delivery. With the discovery and characterization of new Cas systems and long noncoding RNA (lncRNA) functional motifs, and because of the compatibility of guide RNA with noncoding RNA elements at multiple sites, it is increasingly possible to solve these problems. In this study, we developed CRISPR signal conductor version 2.0 by integrating various lncRNA functional motifs into different parts of the crRNA in the CRISPR-dCasΦ system. This system can directly regulate the expression of target genes by recruiting cellular endogenous transcription factors and efficiently sense a variety of protein signals that are not detected by a classical synthetic system. The new system solved the problems of background leakage and insensitive signaling responses and enabled the construction of logic gates with as many as six input signals, which can be used to specifically target cancer cells. By rewiring endogenous signaling networks, we further demonstrated the effectiveness and biosafety of this system for in vivo cancer gene therapy.
•Near room temperature (205.44, 200.45, and 287.88 K) p-orbital 2D multiferroic materials single-layer XN (X = Ge, Sn, Pb) are predicted.•TC of single-layer XN (X = Ge, Sn, Pb) can be further ...respectively increased to 225.39, 245.35, and 369.99 K by in-plane biaxial strain.•In addition, biaxial strain can induce the transition from semiconductor to half-metal and ferroelectric to paraelectric in a single layer.
Two-dimensional (2D) multiferroic materials have triggered a burst of interest owing to their wide applications in nanoelectronics. Specifically, p-orbital multiferroicity is strongly desired but has been very few reported. Here, based on first-principles calculations, we unveil a new type of 2D multiferroic material: the single-layer (SL) XN (X = Ge, Sn, Pb). Our findings show these materials are ferromagnetic semiconductors with strong magnetoelectric coupling and wide bandgaps. The multiferroicity is related to the unpaired p-orbital electrons of N atoms and the buckled crystal structure. All the single layers show easy-plane magnetocrystalline anisotropy, and the magnetic anisotropy energy increases significantly with the atomic number increasing. Our Monte Carlo simulations suggest the Curie temperature TC is 205.44 K, 200.45 K, and 287.88 K for SL GeN, SnN, and PbN, respectively. By applying tensile strain, the TC can be further increased to 225.39 K, 245.35 K, 369.99 K, respectively. Additionally, biaxial strain can induce semiconductor-to-half-metal and ferroelectricity-to-paraelectricity transition in the single layers. We aspire that our work contributes to the exploration of room-temperature p-orbital multiferroicity.
Background
Studies on biological functions of N6‐methyladenosine (m6A) modification in mRNA have sprung up in recent years. Previous studies have reported m6A can determine mRNA fate and play a ...pivotal role in tumour development and progression. The zinc finger protein 677 (ZNF677) belongs to the zinc finger protein family and possesses transcription factor activity by binding sequence‐specific DNA.
Methods
The expression of ZNF677 and its clinicopathological impact were evaluated in renal cell carcinoma (RCC) patients. The m6A level of ZNF677 was determined by m6A methylated RNA immunoprecipitation‐sequencing (MeRIP‐seq) and MeRIP‐qPCR in RCC tissues and adjacent normal tissues. RNA immunoprecipitation‐qPCR (RIP‐qPCR) and luciferase assays were performed to identify the targeted effect of IGF2BP2 and YTHDF1 on ZNF677. RCC cells and subcutaneous models uncovered the role of ZNF677 methylated by CRISPR/dCas13b‐METTL3 in tumour growth. ZNF677‐binding sites in the CDKN3 promoter were investigated by chromatin immunoprecipitation (ChIP) and luciferase assays.
Results
ZNF677 is frequently downregulated in RCC tissues and its low expression is associated with unfavourable prognosis and decreased m6A modification level. Further, we find the m6A‐modified coding sequence (CDS) of ZNF677 positively regulates its translation and mRNA stability via binding with YTHDF1 and IGF2BP2, respectively. Targeted specific methylation of ZNF677 m6A by CRISPR/dCas13b‐METLL3 system can significantly increase the m6A and expression level of ZNF677, and dramatically inhibit cell proliferation and induce cell apoptosis of RCC cells. In addition, ZNF677 exerted its tumour suppressor functions in RCC cells through transcriptional repression of CDKN3 via binding to its promoter. In vitro and clinical data confirm the negative roles of ZNF677/CDKN3 in tumour growth and progression of RCC.
Conclusion
ZNF677 functions as a tumour suppressor and is frequently silenced via m6A modification in RCC, which may highlight m6A methylation‐based approach for RCC diagnosis and therapy.
ZNF677 is frequently silenced via m6A modification in RCC.
The m6A modified CDS of ZNF677 positively regulates its translation and stability via binding with YTHDF1 and IGF2BP2, respectively.
ZNF677 exerted its tumor suppressor functions in RCC cells through transcriptional repression of CDKN3 via binding to its promoter.
N
6
-Methyladenosine (m
6
A) is the most widespread internal RNA modification in several species. In spite of latest advances in researching the biological roles of m
6
A, its function in the ...development and progression of bladder cancer remains unclear. In this study, we used MeRIPty -55-seq and RNA-seq methods to obtain a comprehensive transcriptome-wide m
6
A profiling and gene expression pattern in bladder cancer and paired normal adjacent tissues. Our findings showed that there were 2,331 hypomethylated and 3,819 hypermethylated mRNAs, 32 hypomethylated and 105 hypermethylated lncRNAs, and 15 hypomethylated and 238 hypermethylated circRNAs in bladder cancer tissues compared to adjacent normal tissues. Furthermore, m
6
A is most often harbored in the coding sequence (CDS), with some near the start and stop codons between two groups. Functional enrichment analysis revealed that differentially methylated mRNAs, lncRNAs, and circRNAs were mostly enriched in transcriptional misregulation in cancer and TNF signaling pathway. We also found that different m
6
A methylation levels of gene might regulate its expression. In summary, our results for the first time provide an m
6
A landscape of human bladder cancer, which expand the understanding of m
6
A modifications and uncover the regulation of mRNAs, lncRNAs, and circRNAs through m
6
A modification in bladder cancer.
Myocardial infarction is the leading cause of death and disability worldwide, and the development of new treatments can help reduce the size of myocardial infarction and prevent adverse ...cardiovascular events. Cardiac repair after myocardial infarction can effectively remove necrotic tissue, induce neovascularization, and ultimately replace granulation tissue. Cardiac inflammation is the primary determinant of whether beneficial cardiac repair occurs after myocardial infarction. Immune cells mediate inflammatory responses and play a dual role in injury and protection during cardiac repair. After myocardial infarction, genetic ablation or blocking of anti-inflammatory pathways is often harmful. However, enhancing endogenous anti-inflammatory pathways or blocking endogenous pro-inflammatory pathways may improve cardiac repair after myocardial infarction. A deficiency of neutrophils or monocytes does not improve overall cardiac function after myocardial infarction but worsens it and aggravates cardiac fibrosis. Several factors are critical in regulating inflammatory genes and immune cells' phenotypes, including DNA methylation, histone modifications, and non-coding RNAs. Therefore, strict control and timely suppression of the inflammatory response, finding a balance between inflammatory cells, preventing excessive tissue degradation, and avoiding infarct expansion can effectively reduce the occurrence of adverse cardiovascular events after myocardial infarction. This article reviews the involvement of neutrophils, monocytes, macrophages, and regulatory T cells in cardiac repair after myocardial infarction. After myocardial infarction, neutrophils are the first to be recruited to the damaged site to engulf necrotic cell debris and secrete chemokines that enhance monocyte recruitment. Monocytes then infiltrate the infarct site and differentiate into macrophages and they release proteases and cytokines that are harmful to surviving myocardial cells in the pre-infarct period. As time progresses, apoptotic neutrophils are cleared, the recruitment of anti-inflammatory monocyte subsets, the polarization of macrophages toward the repair phenotype, and infiltration of regulatory T cells, which secrete anti-inflammatory factors that stimulate angiogenesis and granulation tissue formation for cardiac repair. We also explored how epigenetic modifications regulate the phenotype of inflammatory genes and immune cells to promote cardiac repair after myocardial infarction. This paper also elucidates the roles of alarmin S100A8/A9, secreted frizzled-related protein 1, and podoplanin in the inflammatory response and cardiac repair after myocardial infarction.
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