This paper offers a general review and comparative analysis of various types of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technologies. It evaluates the strengths and weaknesses of these techn...This paper offers a general review and comparative analysis of various types of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technologies. It evaluates the strengths and weaknesses of these technologies to identify the optimal approach for conducting genetic screens. Through an extensive literature review, this paper examines CRISPR nuclease, CRISPR activation (CRISPRa), and CRISPR interference (CRISPRi) screens. This study concludes that CRISPRa and CRISPRi are more advantageous due to their use of deactivated Cas9 proteins that only over-express or deactivate genes rather than irreversibly breaking genes like CRISPRn. Notably, CRISPRa is unique in its ability to over-express genes, while the other two technologies deactivate genes. Future studies may focus on inducing multiple mutations simultaneously—both gain-of-function and gene knockout—to carry out a more complete screen that can test the combinatorial effect of genes. Likewise, targeting both exons and introns can offer a more thorough understanding of a specific phenotype.展开更多
Metamorphosis is a complex developmental process involving multiple pathways and a large number of genes that are regulated by juvenile hormone(JH)and 20-hydroxyecdysone(20E).Despite important progress in understandin...Metamorphosis is a complex developmental process involving multiple pathways and a large number of genes that are regulated by juvenile hormone(JH)and 20-hydroxyecdysone(20E).Despite important progress in understanding various aspects of silkworm biology,the hormone signaling pathway in the silkworm remains poorly understood.Genome-wide screening using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-based libraries has recently emerged as a novel method for analyzing genome function,enabling further research into essential genes,drug targets,and virus-host interaction.Previously,we constructed a genome-wide CRISPR/Cas9-based library of the silkworm(Bombyx mori)and successfully revealed the genes involved in biotic or abiotic stress factor responses.In this study,we used our silkworm CRISPR library and large-scale genome-wide screening to analyze the key genes in the silkworm 20E signaling pathway and their mechanisms of action.Functional annotation showed that 20E regulates key proteins in processes that mainly occur in the cytoplasm and nucleus.Pathway enrichment analysis showed that 20E can activate phosphorylation and may affect innate immunity,interfere with intracellular nutrition and energy metabolism,and eventually cause cell apoptosis.The screening results were experimentally validated by generating cells with knockout alleles of the relevant genes,which had increased tolerance to 20E.Our findings provide a panoramic overview of signaling in response to 20E in the silkworm,underscoring the utility of genome-wide CRISPR mutant libraries in deciphering hormone signaling pathways and the mechanisms that regulate metamorphosis in insects.展开更多
Metformin is currently a strong candidate anti-tumor agent in multiple cancers.However,its anti-tumor effectiveness varies among different cancers or sub-populations,potentially due to tumor heterogeneity.It thus rema...Metformin is currently a strong candidate anti-tumor agent in multiple cancers.However,its anti-tumor effectiveness varies among different cancers or sub-populations,potentially due to tumor heterogeneity.It thus remains unclear which hepatocellular carcinoma(HCC)patient subpopulation(s)can benefit from met-formin treatment.Here,through a genome-wide CRISPR-Cas9-based knockout screen,we find that DOCK1 levels determine the anti-tumor effects of met-formin and that DOCK1 is a synthetic lethal target of metformin in HCC.Mechanistically,metformin promotes DOCK1 phosphorylation,which activates RAC1 to facilitate cell survival,leading to metformin resistance.The DOCK1-selective inhibitor,TBOPP,potentiates anti-tumor activity by metformin in vitro in liver cancer cell lines and patient-derived HCC organoids,and in vivo in xenografted liver cancer cells and immunocompetent mouse liver cancer models.Notably,metformin improves overall survival of HCC patients with low DOCK1 levels but not among patients with high DOCK1 expression.This study shows that metformin effective-ness depends on DOCK1 levels and that combining metformin with DOCK1 inhibition may provide a promising personalized therapeutic strategy for met-formin-resistant HCC patients.展开更多
BRAF is a serine/threonine kinase that harbors activating mutations in^7%of human malignancies and^60%of melanomas.Despite initial clinical responses to BRAF inhibitors,patients frequently develop drug resistance.To i...BRAF is a serine/threonine kinase that harbors activating mutations in^7%of human malignancies and^60%of melanomas.Despite initial clinical responses to BRAF inhibitors,patients frequently develop drug resistance.To identify candidate therapeutic targets for BRAF inhibitor resistant melanoma,we conduct CRISPR screens in melanoma cells harboring an activating BRAF mutation that had also acquired resistance to BRAF inhibitors.To investigate the mechanisms and pathways enabling resistance to BRAF inhibitors in melanomas,we integrate expression,ATAC-seq,and CRISPR screen data.We identify the JUN family transcription factors and the ETS family transcription factor ETV5 as key regulators of CDK6,which together enable resistance to BRAF inhibitors in melanoma cells.Our findings reveal genes contributing to resistance to a selective BRAF inhibitor PLX4720,providing new insights into gene regulation in BRAF inhibitor resistant melanoma cells.展开更多
Background:Pooled CRISPR screen is a promising tool in drug targets or essential genes identification with the utilization of three different systems including CRISPR knockout(CRISPRko),CRISPR interference(CRISPRi)and...Background:Pooled CRISPR screen is a promising tool in drug targets or essential genes identification with the utilization of three different systems including CRISPR knockout(CRISPRko),CRISPR interference(CRISPRi)and CRISPR activation(CRISPRa).Aside from continuous improvements in technology,more and more bioinformatics methods have been developed to analyze the data obtained by CRISPR screens which facilitate better understanding of physiological effects.Results:Here,we provide an overview on the application of CRISPR screens and bioinformatics approaches to analyzing different types of CRISPR screen data.We also discuss mechanisms and underlying challenges for the analysis of dropout screens,sorting-based screens and single-cell screens.Conclusion:Different analysis approaches should be chosen based on the design of screens.This review will help community to better design novel algorithms and provide suggestions for wet-lab researchers to choose from different analysis methods.展开更多
The regulation of protein stability is a fundamental issue for biophysical processes,but there has not previously been a convenient and unbiased method of identifying regulators of protein stability.However,as reporte...The regulation of protein stability is a fundamental issue for biophysical processes,but there has not previously been a convenient and unbiased method of identifying regulators of protein stability.However,as reported in the article entitled "A genome-scale CRISPR-Cas9 screening method for protein stability reveals novel regulators of Cdc25 A," recently published in Cell Discovery,our team developed a protein stability regulators screening assay(Pro-SRSA) by combining the whole-genome clustered regularly interspaced short palindromic repeats Cas9(CRISPR-Cas9) library with a dual-fluorescence-based protein stability reporter and high-throughput sequencing to screen for regulators of protein stability.Based on our findings,we are confident that this efficient and unbiased screening method at the genome scale will be used by researchers worldwide to identify regulators of protein stability.展开更多
Targeted mutagenesis based on homologous recombination has been a powerful tool for understanding the mechanisms underlying development, normal physiology, and disease. A recent breakthrough in genome engineering tech...Targeted mutagenesis based on homologous recombination has been a powerful tool for understanding the mechanisms underlying development, normal physiology, and disease. A recent breakthrough in genome engineering technology based on the class of RNA-guided endonucleases, such as clustered regularly interspaced short palindromic repeats(CRISPR)-associated Cas9, is further revolutionizing biology and medical studies. The simplicity of the CRISPR-Cas9 system has enabled its widespread applications in generating germline animal models, somatic genome engineering, and functional genomic screening and in treating genetic and infectious diseases. This technology will likely be used in all fields of biomedicine, ranging from basic research to human gene therapy.展开更多
文摘This paper offers a general review and comparative analysis of various types of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technologies. It evaluates the strengths and weaknesses of these technologies to identify the optimal approach for conducting genetic screens. Through an extensive literature review, this paper examines CRISPR nuclease, CRISPR activation (CRISPRa), and CRISPR interference (CRISPRi) screens. This study concludes that CRISPRa and CRISPRi are more advantageous due to their use of deactivated Cas9 proteins that only over-express or deactivate genes rather than irreversibly breaking genes like CRISPRn. Notably, CRISPRa is unique in its ability to over-express genes, while the other two technologies deactivate genes. Future studies may focus on inducing multiple mutations simultaneously—both gain-of-function and gene knockout—to carry out a more complete screen that can test the combinatorial effect of genes. Likewise, targeting both exons and introns can offer a more thorough understanding of a specific phenotype.
基金This work was supported by grants from the National Natural Science Foundation of China(No.32122084)Chongqing Natural Science Foundation(No.cstc2021ycjh-bgzxm0005)+1 种基金PhD Start-Up Foundation of Southwest University(No.SWU120012)Fundamental Research Funds for the Central Universities(No.SWU-KT22042).None of these fundings played any role in the design of the study,collection,analysis,or interpretation of data or in the writing of the manuscript.
文摘Metamorphosis is a complex developmental process involving multiple pathways and a large number of genes that are regulated by juvenile hormone(JH)and 20-hydroxyecdysone(20E).Despite important progress in understanding various aspects of silkworm biology,the hormone signaling pathway in the silkworm remains poorly understood.Genome-wide screening using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-based libraries has recently emerged as a novel method for analyzing genome function,enabling further research into essential genes,drug targets,and virus-host interaction.Previously,we constructed a genome-wide CRISPR/Cas9-based library of the silkworm(Bombyx mori)and successfully revealed the genes involved in biotic or abiotic stress factor responses.In this study,we used our silkworm CRISPR library and large-scale genome-wide screening to analyze the key genes in the silkworm 20E signaling pathway and their mechanisms of action.Functional annotation showed that 20E regulates key proteins in processes that mainly occur in the cytoplasm and nucleus.Pathway enrichment analysis showed that 20E can activate phosphorylation and may affect innate immunity,interfere with intracellular nutrition and energy metabolism,and eventually cause cell apoptosis.The screening results were experimentally validated by generating cells with knockout alleles of the relevant genes,which had increased tolerance to 20E.Our findings provide a panoramic overview of signaling in response to 20E in the silkworm,underscoring the utility of genome-wide CRISPR mutant libraries in deciphering hormone signaling pathways and the mechanisms that regulate metamorphosis in insects.
基金supported in part by National Key R&D Program of China(2018YFA0107103,2018YFA0800300)the Chinese Academy of Sciences(XDB39000000)+3 种基金National Natural Science Foundation of China(81930083,91957203,81821001,81525022)Outstanding Scholar Program of Guangzhou Regenerative Medicine and Health Guangdong Laboratory(2018GZR110102001)the Program for Guangdong Introducing Innovative and Entrepreneurial Teams(2017ZT07S054)the Fundamental Research Funds for the Central Universities(YD2070002008,2020ZYGXZR038).
文摘Metformin is currently a strong candidate anti-tumor agent in multiple cancers.However,its anti-tumor effectiveness varies among different cancers or sub-populations,potentially due to tumor heterogeneity.It thus remains unclear which hepatocellular carcinoma(HCC)patient subpopulation(s)can benefit from met-formin treatment.Here,through a genome-wide CRISPR-Cas9-based knockout screen,we find that DOCK1 levels determine the anti-tumor effects of met-formin and that DOCK1 is a synthetic lethal target of metformin in HCC.Mechanistically,metformin promotes DOCK1 phosphorylation,which activates RAC1 to facilitate cell survival,leading to metformin resistance.The DOCK1-selective inhibitor,TBOPP,potentiates anti-tumor activity by metformin in vitro in liver cancer cell lines and patient-derived HCC organoids,and in vivo in xenografted liver cancer cells and immunocompetent mouse liver cancer models.Notably,metformin improves overall survival of HCC patients with low DOCK1 levels but not among patients with high DOCK1 expression.This study shows that metformin effective-ness depends on DOCK1 levels and that combining metformin with DOCK1 inhibition may provide a promising personalized therapeutic strategy for met-formin-resistant HCC patients.
基金supported by grants from the National Natural Science Foundation of China(Grant No.81872290)the National Key R&D Program of China(Grant No.2017YFC0908500)
文摘BRAF is a serine/threonine kinase that harbors activating mutations in^7%of human malignancies and^60%of melanomas.Despite initial clinical responses to BRAF inhibitors,patients frequently develop drug resistance.To identify candidate therapeutic targets for BRAF inhibitor resistant melanoma,we conduct CRISPR screens in melanoma cells harboring an activating BRAF mutation that had also acquired resistance to BRAF inhibitors.To investigate the mechanisms and pathways enabling resistance to BRAF inhibitors in melanomas,we integrate expression,ATAC-seq,and CRISPR screen data.We identify the JUN family transcription factors and the ETS family transcription factor ETV5 as key regulators of CDK6,which together enable resistance to BRAF inhibitors in melanoma cells.Our findings reveal genes contributing to resistance to a selective BRAF inhibitor PLX4720,providing new insights into gene regulation in BRAF inhibitor resistant melanoma cells.
基金This study was supported by the Shear Family Foundation(to D.Y.),the American Cancer Society Research Scholar Award(132632-RSG-18-179-01-RMC to D.Y.)National Cancer Institute(1R01CA222274 and R01CA255196 to D.Y.).
文摘Background:Pooled CRISPR screen is a promising tool in drug targets or essential genes identification with the utilization of three different systems including CRISPR knockout(CRISPRko),CRISPR interference(CRISPRi)and CRISPR activation(CRISPRa).Aside from continuous improvements in technology,more and more bioinformatics methods have been developed to analyze the data obtained by CRISPR screens which facilitate better understanding of physiological effects.Results:Here,we provide an overview on the application of CRISPR screens and bioinformatics approaches to analyzing different types of CRISPR screen data.We also discuss mechanisms and underlying challenges for the analysis of dropout screens,sorting-based screens and single-cell screens.Conclusion:Different analysis approaches should be chosen based on the design of screens.This review will help community to better design novel algorithms and provide suggestions for wet-lab researchers to choose from different analysis methods.
基金supported by grants from the Key Project of Guangzhou(No.1561000151)the Yangtze River Scholarship(No.85000-52121100)+1 种基金the National Nature Science Foundation in China(No.81530081,31571395)the 973 project(No.2012CB967000)
文摘The regulation of protein stability is a fundamental issue for biophysical processes,but there has not previously been a convenient and unbiased method of identifying regulators of protein stability.However,as reported in the article entitled "A genome-scale CRISPR-Cas9 screening method for protein stability reveals novel regulators of Cdc25 A," recently published in Cell Discovery,our team developed a protein stability regulators screening assay(Pro-SRSA) by combining the whole-genome clustered regularly interspaced short palindromic repeats Cas9(CRISPR-Cas9) library with a dual-fluorescence-based protein stability reporter and high-throughput sequencing to screen for regulators of protein stability.Based on our findings,we are confident that this efficient and unbiased screening method at the genome scale will be used by researchers worldwide to identify regulators of protein stability.
文摘利用功能缺失型(Loss-of-function)或者功能获得型(Gain-of-function)策略高通量筛选功能基因,是研究人员快速寻找调控特定表型的重要或关键基因的主要方法。RNA干扰(RNA interference,RNAi)的遗传筛选方法因操作简单、成本相对较低等优势,尽管已经得到了广泛的应用,然而其抑制效果不完全、脱靶效应明显等劣势依然存在。近年来兴起的CRISPR/Cas9(Clustered regularly interspaced short palindromic repeat sequences/CRISPR-associated protein 9)技术能快速、简便、准确地实现基因组敲除等编辑功能,因而成为一种强大的遗传筛选工具;在各种细胞系、人和小鼠及斑马鱼等多种模式动物中,大规模运用该方法筛选功能基因已经取得了巨大成功。本文总结了CRISPR/Cas9技术的特点,将其与传统基因工程方法进行了分析比较,回顾了近期相关的高通量功能基因筛选工作,最后探讨了该技术未来的发展趋势。
基金supported by the Chinese National Key Program on Basic Research (2012CB945103, 2011CB504202)National Natural Science Foundation of China (31430057)
文摘Targeted mutagenesis based on homologous recombination has been a powerful tool for understanding the mechanisms underlying development, normal physiology, and disease. A recent breakthrough in genome engineering technology based on the class of RNA-guided endonucleases, such as clustered regularly interspaced short palindromic repeats(CRISPR)-associated Cas9, is further revolutionizing biology and medical studies. The simplicity of the CRISPR-Cas9 system has enabled its widespread applications in generating germline animal models, somatic genome engineering, and functional genomic screening and in treating genetic and infectious diseases. This technology will likely be used in all fields of biomedicine, ranging from basic research to human gene therapy.
