Application of Artificially Induced Double-strand Breaks (DSB) and Triplex-forming Oligonucleotides (TFO) in the Improvement of Gene Targeting Efficiency

Gene targeting technology is an important means to investigate gene functions, but its efficiency of gene targeting is very low, especially for somatic cell targeting. Artificially induced double-strand breaks （DSB） and triplex forming oligonucleotide （TFO） are currently developed methods to improve the targeting efficiency. This paper summarized the basic principles, design ideas and application in gene targeting efficiency improvement of these two methods, analyzed and com- pared their characteristics, and finally proposed prospects for their future development.

Characterization of blueberry exosome-like nanoparticles and miRNAs with potential cross-kingdom human gene targets

Edible plant derived exosome-like nanoparticles(ELNs)have been shown to have multiple nutraceutical functions.However,the diversity of plant materials makes the plant derived ELN study challenging.More efforts are still needed to explore the feasible isolation methods of edible plant derived ELNs and the possible roles of food-derived ELNs in improving human health.In this study,a size exclusion chromatography based method was compared with the traditional ultracentrifugation method to isolate blueberry derived ELNs(B-ELNs),and the miRNA profile of B-ELNs was analyzed by high-throughput sequencing.A total of 36 miRNAs were found to be enriched in B-ELNs compared with berry tissue,and their potential cross-kingdom human gene targets were further predicted.Results showed that size exclusion chromatography was effective for B-ELN isolation.The most abundant miRNAs in B-ELNs mainly belonged to the miR166 family and miR396 family.Target gene prediction indicated that B-ELNs could potentially regulate pathways related to the human digestive system,immune system and infectious diseases.

To Analyze the Sensitivity of RT-PCR Assays Employing S Gene Target Failure with Whole Genome Sequencing Data during Third Wave by SARS-CoV-2 Omicron Variant

Introduction: Omicron is a highly divergent variant of concern (VOCs) of a severe acute respiratory syndrome SARS-CoV-2. It carries a high number of mutations in its spike protein hence;it is more transmissible in the community by immune evasion mechanisms. Due to mutation within S gene, most Omicron variants have reported S gene target failure (SGTF) with some commercially available PCR kits. Such diagnostic features can be used as markers to screen Omicron. However, Whole Genome Sequencing (WGS) is the only gold standard approach to confirm novel microorganisms at genetically level as similar mutations can also be found in other variants that are circulating at low frequencies worldwide. This Retrospective study is aimed to assess RT-PCR sensitivity in the detection of S gene target failure in comparison with whole genome sequencing to detect variants of Omicron. Methods: We have analysed retrospective data of SARS-CoV-2 positive RT-PCR samples for S gene target failure (SGTF) with TaqPath COVID-19 RT-PCR Combo Kit (ThermoFisher) and combined with sequencing technologies to study the emerged pattern of SARS-CoV-2 variants during third wave at the tertiary care centre, Surat. Results: From the first day of December 2021 till the end of February 2022, a total of 321,803 diagnostic RT-PCR tests for SARS-CoV-2 were performed, of which 20,566 positive cases were reported at our tertiary care centre with an average cumulative positivity of 6.39% over a period of three months. In the month of December 21 samples characterized by the SGTF (70/129) were suggestive of being infected by the Omicron variant and identified as Omicron (B.1.1.529 lineage) when sequence. In the month of January, we analysed a subset of samples (n = 618) with SGTF (24%) and without SGTF (76%) with Ct values Conclusions: During the COVID-19 pandemic, it took almost more than 15 days to diagnose infection and identify pathogen by sequencing technology. In contrast to that molecular assay provided quick identification with the help of SGTF phenomenon within 5 hours of duration. This strategy helps scientists and health policymakers for the quick isolation and identification of clusters. That ultimately results in a decreased transmission of pathogen among the community.

Site-Specifc Gene Targeting Using Transcription Activator-Like Effector(TALE)-Based Nuclease in Brassica oleracea

Site-specific recognition modules with DNA nuclease have tremendous potential as molecular tools for genome targeting. The type III transcription activator-like effectors （TALEs） contain a DNA binding domain consisting of tandem repeats that can be engineered to bind user-defined specific DNA sequences. We demonstrated that customized TALE-based nucleases （TALENs）, constructed using a method called ＂unit assembly＂, specifically target the endogenous FRIGIDA gene in Brassica oleracea L. var. capitata L. The results indicate that the TALENs bound to the target site and cleaved double-strand DNA in vitro and in vivo, whereas the effector binding elements have a 23 bp spacer. The T7 endonuclease I assay and sequencing data show that TALENs made double-strand breaks, which were repaired by a non- homologous end-joining pathway within the target sequence. These data show the feasibility of applying customized TALENs to target and modify the genome with deletions in those organisms that are still in lacking gene target methods to provide germplasms in breeding improvement.

Efficient Gene Targeting in Zebrafish Mediated by a Zebrafish-Codon-Optimized Cas9 and Evaluation of Off-Targeting Effect

Targeted genome modifications with the Cas9/gRNA system derived from the clustered regularly interspaced short palin- dromic repeat/CRISPR-associated （CRISPR/Cas） system have been successfully used in cultured human cells as well as in most model organisms, including zebrafish （Danio rerio）, mouse, and fruit fly （Chang et al., 2013; Cong et al., 2013; Gratz et al., 2013; Hwang et al., 2013; Jao et al., 2013; Shen et al., 2013; Wei et al., 2013）. Its application in zebrafish is particu- larly attractive due to the ease of handling this organism and the simple application of this method by direct injection of Cas9/ gRNA. However, the information about its specificity in this organism is very limited and needs further evaluation. In addition, it is conceivable that a Cas9 mRNA optimized for zebrafish codon preference could enhance its activity.

Advances in Drosophila gene targeting and related techniques

Functional biological research has benefited tremendously by analyses of the phenotypes of mutant organisms which can be generated through targeted mutation of genes.In Drosophila,compared with random mutagenesis methods gene targeting has gained its popularity because it can introduce any desired mutation into a gene of interest.However,applications of gene targeting have been limited because the targeting efficiency varies with different genes,and the time and labor of targeting procedure are intensive.Nevertheless,improvement of gene targeting and development of its variant technologies have received much attention of scientists.Here we review recent progress that has been made in expanding the applications of gene targeting,which include the ϕC31 integration system and zinc-finger nucleases induced gene targeting,and new strategies that generate more efficient and reliable gene targeting.

Comparison of Two Construction Methods of Targeting Gene of Haemophilus parasuis

Haemophilus parasuis is one kind of constant bacteria in porcine upper respiratory tract, and it can cause multiple serositis, arthritis and other diseases under certain conditions. Due to lack of efficient genetic operating system, its pathogenic mechanism is not very clear. Ligation with DNA ligase and fusion PCR were used to construct targeting hhdA gene of Haemophilus parasuis, respectively. The fidelity, application scope, operation and conditions of the constructed fusion fragments were compared. The results showed that construction with DNA ligase was more mature technology as manifested by more stable conditions and more extensive application. The fusion PCR method had high fidelity and simple operation, and the transformation rate was 9.5 times as high as that of ligation with DNA ligase. For this reason, this method was more suitable for construction of multi-fragment targeting genes. The study lays a foundation for establishing an efficient operating system of targeting gene of Haemophilus parasuis in the future.

Gene targeted and immune therapies for nodal and gastrointestinal follicular lymphomas

Follicular lymphoma(FL)is the most common indolent B-cell lymphoma(BCL)globally.Recently,its incidence has increased in Europe,the United States,and Asia,with the number of gastrointestinal FL cases expected to increase.Genetic abnormalities related to t(14;18)translocation,BCL2 overexpression,NF-κB pathway-related factors,histone acetylases,and histone methyltransferases cause FL and enhance its proliferation.Meanwhile,microRNAs are commonly used in diagnosing FL and predicting patient prognosis.Many clinical trials on novel therapeutics targeting these genetic abnormalities and immunomodulatory mechanisms have been conducted,resulting in a marked improvement in therapeutic outcomes for FL.Although developing these innovative therapeutic agents targeting specific genetic mutations and immune pathways has provided hope for curative options,FL treatment has become more complex,requiring combinatorial therapeutic regimens.However,optimal treatment combinations have not yet been achieved,highlighting the importance of a complete understanding regarding the pathogenesis of gastrointestinal FL.Accordingly,this article reviews key research on the molecular pathogenesis of nodal FL and novel therapies targeting the causative genetic mutations.Moreover,the results of clinical trials are summarized,with a particular focus on treating nodal and gastrointestinal FLs.

阿帕替尼治疗腺样囊性癌肺转移1例

腺样囊性癌(adenoid cystic carcinoma,ACC)是一种较少见的来源于腺体的恶性肿瘤,约占头颈部恶性肿瘤的1%[1]。其病程进展缓慢但极易侵袭,有较高的复发率和远处转移率,最常见的转移部位是肺[2]。对于ACC肺转移患者,目前并无特效药物。MYB基因表达失调是ACC患者最常见的突变。

Loss of canonical Wnt signaling is involved in the pathogenesis of Alzheimer's disease

Alzheimer＇s disease（AD） is the most common form of dementia in the older population, however, the precise cause of the disease is unknown. The neuropathology is characterized by the presence of aggregates formed by amyloid-β（Aβ） peptide and phosphorylated tau; which is accompanied by progressive impairment of memory. Diverse signaling pathways are linked to AD, and among these the Wnt signaling pathway is becoming increasingly relevant, since it plays essential roles in the adult brain. Initially, Wnt signaling activation was proposed as a neuroprotective mechanism against Aβ toxicity. Later, it was reported that it participates in tau phosphorylation and processes of learning and memory. Interestingly, in the last years we demonstrated that Wnt signaling is fundamental in amyloid precursor protein（APP） processing and that Wnt dysfunction results in Aβ production and aggregation in vitro. Recent in vivo studies reported that loss of canonical Wnt signaling exacerbates amyloid deposition in a transgenic（Tg） mouse model of AD. Finally, we showed that inhibition of Wnt signaling in a Tg mouse previously at the appearance of AD signs, resulted in memory loss, tau phosphorylation and Aβ formation and aggregation; indicating that Wnt dysfunction accelerated the onset of AD. More importantly, Wnt signaling loss promoted cognitive impairment, tau phosphorylation and Aβ1–42 production in the hippocampus of wild-type（WT） mice, contributing to the development of an Alzheimer＇s-like neurophatology. Therefore, in this review we highlight the importance of Wnt/β-catenin signaling dysfunction in the onset of AD and propose that the loss of canonical Wnt signaling is a triggering factor of AD.

Screening ulcerative colitis key target gene and pathway based on KEGG pathway

Objective:To obtain the relevant information of pathway and gene by using the database of DAVID,analyze the function and distribution of important genes,screen out the target genes related to Ulcerative Colitis and promote the study of the pathogenesis of UC and the development of new drugs.Methods:The Ulcerative Colitis was used to search UC related genes in TTD,Drugbank,DisGeNET database.The obtained gene data was input to the database of Daved,and the data of gene enriched pathway was obtained 87 genes were Significant enriched in the first 20 KEGG pathways.The 87 genes were input to the string database to make the interaction network diagram,and the key genes enriched in the pathway were also made the network diagram,and the two network diagrams were compared.Results:RELA,TNF,IL1B,NFKB1,IL6 and IL10 were among the highest ranked genes in two network diagrams.Conclusion:The study of RELA,TNF,IL1B,NFKB1,IL6 and IL10 is necessary for us to study further.The pathogenesis of UC was associated with multiple pathways such as NF-kappa B signaling pathway,Jak-STAT signaling pathway,TNF signaling pathway and so on.It is helpful to understand the pathogenesis of disease and provide a reliable target for the development of new drugs by analyzing the pathway and the network diagram of the interaction between genes and disease related genes.

Targeted mutagenesis of amino acid transporter genes for rice quality improvement using the CRISPR/Cas9 system

High grain protein content(GPC) reduces rice eating and cooking quality(ECQ). We generated OsAAP6 and OsAAP10 knockout mutants in three high-yielding japonica varieties and one japonica line using the CRISPR/Cas9 system. Mutation efficiency varied with genetic background in the T_0 generation, and GPC in the T_1 generation decreased significantly,owing mainly to a reduction in glutelin content. Amylose content was down-regulated significantly in some Osaap6 and all Osaap10 mutants. The increased taste value of these mutants was supported by Rapid Visco Analysis(RVA) profiles, which showed higher peak viscosity and breakdown viscosity and lower setback viscosity than the wild type. There were no significant deficiencies in agronomic traits of the mutants. Targeted mutagenesis of OsAAP6 and OsAAP10, especially OsAAP10, using the CRISPR/Cas9 system can rapidly reduce GPC and improve ECQ of rice, providing a new strategy for the breeding cultivars with desired ECQ.

Role of microRNA in liver regeneration

BACKGROUND： Liver regeneration is a complex process. micro RNAs（mi RNAs） are short, single-stranded RNAs that modify gene expression at the post-transcriptional level. Recent investigations have revealed that mi RNAs are closely linked to liver regeneration.DATA SOURCES： All included studies were obtained from Pub Med, Embase, the Science Direct databases and Web of Science, with no limitation on publication year. Only studies published in English were considered.RESULTS： We grouped studies that involved mi RNA and liver regeneration into two groups： mi RNAs as promoters and as inhibitors of liver regeneration. We summarized the relevant mi RNAs separately from the related pathways.CONCLUSIONS： Blocking or stimulating the pathways of mi RNAs in liver regeneration may be novel therapeutic strategies in future regeneration-related liver managements. We may discover additional chemotherapy targets of mi RNA.

Screening key target genes for pulmonary arterial hypertension based on bioinformatics

Background:Screening key target genes for pulmonary arterial hypertension(PAH)based on bioinformatics to provide a reference for the clinical development of drugs to cure PAH.Methods:The keyword“pulmonary arterial hypertension”was used to search related genes in the National Center for Biotechnology Information database(NCBI).The obtained genes data was input to the database of Database for Annotation,Visualization and Integrated Discovery(DAVID)(Version 6.8)to collect relevant information about pathways and genes.And the data of genes were enriched in 37 pathways and genes with occurrence frequency≥10 were respectively imported into the String database to construct protein-protein interaction(PPI)network diagrams,and the two network diagrams were compared.Results:VEGFA,MAPK1,MAPK3,IL6,JUN and TNF were among the highest-ranked genes in two network diagrams.Conclusion:The pathogenesis of PAH is associated with multiple pathways such as the TGF-βsignaling pathway,PI3K-Akt signaling pathway,MAPK signaling pathway,HIF-1 signaling pathway and so on.The study of VEGFA,MAPK1,MAPK3,IL6,JUN and TNF are closely related to PAH is necessary for us to study further.Through gene interaction network and pathway analysis of disease-associated genes,which will help us to screen the critical target genes of PAH and provide a reference for clinical development of effective drugs for PAH.

Phylogenetic analysis and target gene prediction of miR477 gene family in grape

To understand the molecular characteristics of the miR477 gene family of grape(Vvi-miR477)and to predict its target genes,the Vvi-miR477 genes were identified from previous small RNA sequencing data,then phylogenetic analysis and prediction of target gene were conducted.The Vvi-miR477 family consists of two precursor sequences and three mature sequences.The miR477 family members were mostly 19-22nt in length.The sequence is relatively conservative.Vvi-MIR477a and Vvi-MIR477b are located on chromosomes 1 and 2,respectively.These precursor sequences can form the typical stable stem-loop structure.Their minimum folding free energy is−39.10 kcal/mol and−50.90 kcal/mol,respectively.The MIR477 family can be divided into three groups.The prediction of target genes showed that Vvi-miR477 targets 26S proteasome,DEAD-box,GRAS family protein,Protein Phosphatase 2C,etc.The GO function of target genes was mainly enriched to six categories.The catabolic process,carboxylic ester hydrolase activity is shown to be high.This study provided a theoretical basis for further exploration of the molecular mechanism of miR477 in grape berry ripening.

Bioinformatics Analysis on Regulatory Mechanism of Peroxisome Proliferator-activated Receptor-γ Gene on Lipid Metabolism

The nuclear receptor peroxisome proliferator-activated receptor γ（PPAR-γ） is a key transcriptional regulator of adipocyte differentiation.It also modulates the synthesis of adipocytokines in the adipose tissue.Its polymorphisms are associated with the risk of type Ⅱ diabetes,obesity,cardiovascular diseases and cancer.In the present study,to investigate the regulatory mechanism of PPAR-γ gene on lipid metabolism,the computational prediction of peroxisome proliferator response elements（PPREs） was pursued with a genome-wide scale by using MEME/MAST method based on the information of TRANSFAC database,then GO and KEGG analyses were carried out.The results showed that a huge number of predicted target genes of PPAR-γ were significantly enriched in 36 GO terms（P〈0.05） and 10 KEGG pathways（P〈0.05） which were related closely to the lipid metabolism.The results should be a valuable resource for elucidation of the regulatory mechanism of PPAR-γ influence on lipid metabolism,also of the major importance to the diagnosis,prevention and treatment of the complex diseases such as obesity and diabete.

Profiling of gene fusion involving targetable genes in Chinese gastric cancer

BACKGROUND Approximately half of all new cases of gastric cancer(GC)and related deaths occur in China.More than 80%of patients with GC are diagnosed at an advanced stage,which results in poor prognosis.Although HER2-directed therapy and immune checkpoint inhibitors have been somewhat successful,new drugs are still needed for the treatment of GC.Notably,several gene fusion-targeted drugs have been approved by the United States Food and Drug Administration for solid tumors,including GC,such as larotrectinib for NTRK fusion-positive cancers and zenocutuzumab for NRG1 fusion-positive cancers.However,gene fusions involving targetable genes have not been well characterized in Chinese patients with GC.AIM To identify the profile of fusions involving targetable genes in Chinese patients with GC using clinical specimens and determine the distribution of patients with gene fusion variants among the molecular subtypes of GC.METHODS We retrospectively analyzed gene fusion events in tumor tissue samples from 954 Chinese patients with GC.Clinicopathological characteristics were obtained from their medical records.Genetic alterations,such as single nucleotide variants,indels,amplifications,and gene fusions,were identified using a targeted sequencing panel containing 825 genes.Fusions were validated by fluorescence in situ hybridization(FISH)using break-apart probes.The microsatellite instability(MSI)status was evaluated using MSIsensor from the targeted sequencing panel data.Tumor mutational burden(TMB)was calculated using the total number of nonsynonymous mutations divided by the total genomic targeted region.Chi-square analysis was used to determine the enrichment of gene fusions associated with the molecular subtypes of GC.RESULTS We found that 1.68%(16/954)of patients harbored 20 fusion events involving targetable genes.RARA fusions(n=5)were the most common,followed by FGFR2,BRAF,MET,FGFR3,RET,ALK,EGFR,NTRK2,and NRG1 fusions.Two of the RARA fusions,EML4-ALK(E6:E20)and EGFRSEPTIN14(E7:E10),have been identified in other tumors but not in GC.Surprisingly,18 gene fusion events were previously not reported in any cancer types.Twelve of the eighteen novel gene fusions included complete exons encoding functional domains of targetable genes,such as the tyrosine kinase domain of receptor tyrosine kinases and the DNA-and ligand-binding domains of RARA.Consistent with the results of detection using the targeted sequencing fusion panel,the results of FISH(fluorescence in situ hybridization)confirmed the rearrangement of FGFR2 and BRAF in tumors from patients 04 and 09,respectively.Genetic analysis indicated that the fusion genes were significantly enriched in patients with ERBB2 amplification(P=0.02);however,there were no significant differences between fusion-positive and fusion-negative patients in age,sex,MSI status,and TMB.CONCLUSION We characterized the landscape of fusions involving targetable genes in a Chinese GC cohort and found that 1.68%of patients with GC harbor potential targetable gene fusions,which were enriched in patients with ERBB2 amplification.Gene fusion detection may provide a potential treatment strategy for patients with GC with disease progression following standard therapy.

Identification and analysis of core target genes of miR-29b-3p in glioma

Objective:To investigate the core target genes of miR-29b-3p,and analyze the clinical significance of the core target genes in glioma.Methods:Bioinformatics analysis was used to predict and screen the target genes of miR-29b-3p.STRING and Cytoscape software were used to analyze the protein-protein interaction(PPI)of target genes.the differences expression and survival prognosis in glioma were analyzed by GEPIA and CGGA.Independent prognostic factors analyzed by univariate and multivariate Cox proportional hazards regression model.Results:22 target genes of miR-29b-3p were predicted using LinkedOmics,miRDB,miRTarBase,TargetScan,and starbase databases.Through the construction of the PPI network,genes out of the network were removed,and a total of 16 genes were screened for further study of their clinical significance.Based on analysis of GEPIA and CGGA databases,COL2A1,DNMT3A,and DNMT3B were excluded.Through further analysis of the univariate and multivariate Cox proportional hazard regression model,finally identified three core target genes:SERPINH1,LOXL2,CDK6.Conclusion:Bioinformatics analysis showed that miR-29b-3p targeted three core genes such as SERPINH1,LOXL2,and CDK6 in glioma.The expression of these genes was different between brain normal tissues and gliomas,between different grades of tumor,IDH mutation status and 1p/19q codeletion status.Its high expression had adverse effects on overall survival and recurrence-free survival.These core target genes can be used as an independent prognostic factor.

Microarray-based Screening of Target Genes Regulated by Heat Shock Factor AtHsfA1a in Arabidopsis thaliana

[ Objective] This study aimed to screen target genes regulated by heat shock factor AtHsfAla in Arabidopsis thaliana. [ Method] Using AtHsfAla-in- serted mutant athsfala （SALK-068042） and wild-type A. thaliana seedlings as experimental materials, target genes regulated by heat shock factor AtHsfAla were screened by microarray assay. Differentially expressed genes were screened by multiple method. Specific functions of differentially expressed genes were analyzed by gene ontology （GO） analysis. Signal transduction pathways, in which differentia｜ly expressed genes were involved, were analyzed by pathway analysis. Gene-gene interaction network was constructed by Signal-Net. [ Result] A total of 3 672 differentially expressed genes were screened out. Up-regulated differentially expressed genes were involved in 198 functions and 7 signal transduction pathways; down-regulated differentially expressed genes were involved in 94 functions and 10 signal transduction pathways. In the signal transduction network, it was found that cwlNV4 and HXK3 had relatively high ability of mediation; AT1 G14240 and cwlNV4 ex- hibited the most interactions with other genes, which were located in key positions throughout the gene-gene interaction network. [ Conclusion] Heat shock factor AtHsfAla regulates a large number of target genes in A. thaliana.

Screening key target genes for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)based on bioinformatics and gene network

Background:To provide a reference for the clinical development of drugs to suppress severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Methods:Retrieving genes related to SARS-CoV-2 with Genecards database and then importing the obtained gene data into the database of Database for Annotation,Visualization and Integrated Discovery(DAVID)(Version 6.8)to collect relevant information on pathways and genes.Genes enriched in the first 20 most significant pathways and genes with gene occurrence frequency≥6 were respectively imported into the STRING database to construct protein-protein interaction(PPI)network diagrams,and the two network diagrams were compared.Results:In the two network graphs,RELA,MAPK1,MAPK3,PIK3CA,PIK3R1,MAPK8,JAK1,STAT1,TNF,IL6,MAPK14,and IL1B ranked higher,and the occurrence frequency of the first 20 pathways was≥10.Conclusion:The pathogenesis of SARS-CoV-2 is associated with multiple pathways such as influenza A,TNF signaling pathway,chemokine signaling pathway,toll-like receptor signaling pathway,T cell receptor signaling pathway et al.RELA,MAPK1,MAPK3,PIK3CA,PIK3R1,MAPK8,JAK1,STAT1,TNF,IL6,MAPK14 and IL1B are closely related to SARS-CoV-2 and need further study.Gene interaction network and pathway analysis of diseaseassociated genes will help us to screen the key target genes of SARS-CoV-2 and provide a reference for the clinical development of effective drugs.