组蛋白赖氨酸乙酰化的识别是组蛋白乙酰化参与表观遗传调控的关键步骤,乙酰化的组蛋白赖氨酸可以被bromodomains(BRDs)结构域所特异性的识别,从而招募染色质调控因子到特定区域,协同完成基因表达调控。其中作用于bromodomain and extra-...组蛋白赖氨酸乙酰化的识别是组蛋白乙酰化参与表观遗传调控的关键步骤,乙酰化的组蛋白赖氨酸可以被bromodomains(BRDs)结构域所特异性的识别,从而招募染色质调控因子到特定区域,协同完成基因表达调控。其中作用于bromodomain and extra-terminal(BET)蛋白家族的BRD结构域的小分子抑制剂在抗炎和抗肿瘤方面显示出巨大的潜力。本文通过对与BET bromodomain靶点相关的疾病、BET bromodomain结构、BET bromodomain小分子抑制剂的化学结构分类及其构效关系等多方面进行总结,为设计和开发高活性的BET bromodomain小分子抑制剂提供参考依据。展开更多
Dear Editor,Ferroptosis,an iron-dependent form of cell death driven by overwhelming lipid peroxidation,represents a vulnerability in cancers,and therapeutic strategies to further potentiate ferroptosis hold great pote...Dear Editor,Ferroptosis,an iron-dependent form of cell death driven by overwhelming lipid peroxidation,represents a vulnerability in cancers,and therapeutic strategies to further potentiate ferroptosis hold great potential for melanoma treatment.展开更多
Proteins usually associate with other molecules physically to execute their functions.Identifying these interactions is important for the functional analysis of proteins.Previously,we reported the parallel analysis of...Proteins usually associate with other molecules physically to execute their functions.Identifying these interactions is important for the functional analysis of proteins.Previously,we reported the parallel analysis of translated ORFs(PLATO)to couple ribosome display of full-length ORFs with affinity enrichment of mRNA/protein/ribosome complexes for the “bait”molecules,followed by the deep sequencing analysis of mRNA.However,the sample processing,from extraction of precipitated mRNA to generation of DNA libraries,includes numerous steps,which is tedious and may cause the loss of materials.Barcoded PLATO(PLATO-BC),an improved platform was further developed to test its application for protein interaction discovery.In this report,we tested the antisera-antigen interaction using serum samples from patients with inclusion body myositis(IBM).Tripartite motif containing 21(TRIM21)was identified as a potentially new IBM autoantigen.We also expanded the application of PLATO-BC to identify protein interactions for JQ1,single ubiquitin peptide,and NS5 protein of Zika virus.From PLATO-BC analyses,we identified new protein interactions for these “bait”molecules.We demonstrate that Ewing sarcoma breakpoint region 1(EWSR1)binds to JQ1 and their interactions may interrupt the EWSR1 association with acetylated histone H4.RIO kinase 3(RIOK3),a newly identified ubiquitin-binding protein,is preferentially associated with K63-ubiquitin chain.We also find that Zika NS5 protein interacts with two previously unreported host proteins,par-3 family cell polarity regulator(PARD3)and chromosome 19 open reading frame 53(C19orf53),whose attenuated expression benefits the replication of Zika virus.These results further demonstrate that PLATO-BC is capable of identifying novel protein interactions for various types of “bait”molecules.展开更多
BACKGROUND The overexpression of the MYC gene plays an important role in the occurrence,development and evolution of colorectal cancer(CRC).Bromodomain and extraterminal domain(BET)inhibitors can decrease the function...BACKGROUND The overexpression of the MYC gene plays an important role in the occurrence,development and evolution of colorectal cancer(CRC).Bromodomain and extraterminal domain(BET)inhibitors can decrease the function BET by recognizing acetylated lysine residues,thereby downregulating the expression of MYC.AIM To investigate the inhibitory effect and mechanism of a BET inhibitor on CRC cells.METHODS The effect of the BET inhibitor JAB-8263 on the proliferation of various CRC cell lines was studied by CellTiter-Glo method and colony formation assay.The effect of JAB-8263 on the cell cycle and apoptosis of CRC cells was studied by propidium iodide staining and Annexin V/propidium iodide flow assay,respectively.The effect of JAB-8263 on the expression of c-MYC,p21 and p16 in CRC cells was detected by western blotting assay.The anti-tumor effect of JAB-8263 on CRC cells in vivo and evaluation of the safety of the compound was predicted by constructing a CRC cell animal tumor model.RESULTS JAB-8263 dose-dependently suppressed CRC cell proliferation and colony formation in vitro.The MYC signaling pathway was dose-dependently inhibited by JAB-8263 in human CRC cell lines.JAB-8263 dose-dependently induced cell cycle arrest and apoptosis in the MC38 cell line.SW837 xenograft model was treated with JAB-8263(0.3 mg/kg for 29 d),and the average tumor volume was significantly decreased compared to the vehicle control group(P<0.001).The MC38 syngeneic murine model was treated with JAB-8263(0.2 mg/kg for 29 d),and the average tumor volume was significantly decreased compared to the vehicle control group(P=0.003).CONCLUSION BET could be a potential effective drug target for suppressing CRC growth,and the BET inhibitor JAB-8263 can effectively suppress c-MYC expression and exert anti-tumor activity in CRC models.展开更多
Switch defective/sucrose non-fermentable(SWI/SNF)chromatin remodeling complexes are multi-subunit machines that play vital roles in the regulation of chromatin structure and gene expression.However,the mechanisms by w...Switch defective/sucrose non-fermentable(SWI/SNF)chromatin remodeling complexes are multi-subunit machines that play vital roles in the regulation of chromatin structure and gene expression.However,the mechanisms by which SWI/SNF complexes recognize their target loci in plants are not fully understood.Here,we show that the Arabidopsis thaliana bromodomain-containing proteins BRD1,BRD2,and BRD13 are core subunits of SWI/SNF complexes and critical for SWI/SNF genomic targeting.These three BRDs interact directly with multiple SWI/SNF subunits,including the BRAHMA(BRM)catalytic subunit.Phenotypic and transcriptomic analyses of the brd1 brd2 brd13 triple mutant revealed that these BRDs act largely redundantly to control gene expression and developmental processes that are also regulated by BRM.Genome-wide occupancy profiling demonstrated that these three BRDs extensively colocalize with BRM on chromatin.Simultaneous loss of function of three BRD genes results in reduced BRM protein levels and decreased occupancy of BRM on chromatin across the genome.Furthermore,we demonstrated that the bromodomains of BRDs are essential for genomic targeting of the BRD subunits of SWI/SNF complexes to their target sites.Collectively,these results demonstrate that BRD1,BRD2,and BRD13 are core subunits of SWI/SNF complexes and reveal their biological roles in facilitating genomic targeting of BRM-containing SWI/SNF complexes in plants.展开更多
The Polybromo （PB） protein functions as a key component of the human PBAF chromatin remodeling complex in regulation of gene transcription. PB is made up of modular domains including six bromodomains that are known ...The Polybromo （PB） protein functions as a key component of the human PBAF chromatin remodeling complex in regulation of gene transcription. PB is made up of modular domains including six bromodomains that are known as acetyl-lysine binding domains. However, histone-binding specificity of the bromodomains of PB has remained elusive. In this study, we report biochemical characterization of all six PB bromodomains＇ binding to a suite of lysine-acetylated peptides derived from known acetylation sites on human core histones. We demonstrate that bromodomain 2 of PB preferentially recognizes acetylated lysine 14 of histone H3 （H3K14ac）, a post-translational mark known for gene transcriptional activation. We further describe the molecular basis of the selective H3K14ac recognition of bromodomain 2 by solving the protein structures in both the free and bound forms using X-ray crystallography and NMR, respectively.展开更多
FgGCN5,a GCN5 homolog in Fusarium graminearum,plays a critical role in hyphal vegetative growth,asexual and sexual reproduction,deoxynivalenol(DON)biosynthesis and plant infection.For nuclear localized GCN5,four conse...FgGCN5,a GCN5 homolog in Fusarium graminearum,plays a critical role in hyphal vegetative growth,asexual and sexual reproduction,deoxynivalenol(DON)biosynthesis and plant infection.For nuclear localized GCN5,four conserved sequence motifs(I-IV)are presented in the catalytic domain and a bromodomain in the carboxy-terminus.As a lysine acetyltransferase,conserved negatively charged residues are present to neutralize the protons from lysine substrates.However,the role of conserved motifs/domains and residues in FgGCN5 are unclear.Here,we generated deletion mutant strains for each the conserved motifs/domains and a glutamate residue 130(E130)replacement mutant.Deletion of each conserved motif in the catalytic domain and replacement of E130 site resulted in manifold defects in hyphae growth,asexual and sexual development,DON biosynthesis,and plant infection.Phenotypic defects in the mutant strains were similar to deletion mutants.The deletion of the bromodomain led a significant reduction in DON production and virulence,with no effects on hyphae growth,asexual or sexual reproduction.FgGCN5 was further found to localize to the nucleus in conidia and hyphae cells.In conclusion,FgGCN5 encodes a nuclear localized acetyltransferase.The conserved motifs in the catalytic domain and E130 are essential for correct functions of the gene.The conserved bromodomain is impotant for DON production and pathogen virulence.This was the first report to identify the functions of conserved motifs/domains in FgGCN5,which will contribute to our understanding of the mechanism(s)by which FgGCN5 regulates F.graminearum.展开更多
组蛋白N末端赖氨酸的乙酰化在转录调控中有重要作用。多种含Bromodomain的蛋白可以与乙酰化赖氨酸结合并招募其它染色质因子来协同调控基因转录,这一过程与人体很多疾病的产生和发展密切相关。本文中对近年来Bromodomain-containing pro...组蛋白N末端赖氨酸的乙酰化在转录调控中有重要作用。多种含Bromodomain的蛋白可以与乙酰化赖氨酸结合并招募其它染色质因子来协同调控基因转录,这一过程与人体很多疾病的产生和发展密切相关。本文中对近年来Bromodomain-containing protein 9(BRD9)选择性的小分子抑制剂的研究进展进行了总结。展开更多
BRPF(bromodomain and PHD finger containing)蛋白作为表观遗传"reader"结构域,能特异性地识别组蛋白"尾部"乙酰化的赖氨酸残基以促进靶基因的转录。本文综述了BPRF蛋白如何识别和结合乙酰赖氨酸标记,讨论了乙酰...BRPF(bromodomain and PHD finger containing)蛋白作为表观遗传"reader"结构域,能特异性地识别组蛋白"尾部"乙酰化的赖氨酸残基以促进靶基因的转录。本文综述了BPRF蛋白如何识别和结合乙酰赖氨酸标记,讨论了乙酰化组蛋白识别对其生物学功能的重要性,以及总结了BRPF bromodomain抑制剂的研究进展。展开更多
Cat's eye syndrome chromosome candidate 2 bromodomain(CECR2 BRD)and Bromodomain PHD transcription factor bromodomain(BPTF BRD)are the same subfamily proteins,both of which are highly conserved in sequence and bind...Cat's eye syndrome chromosome candidate 2 bromodomain(CECR2 BRD)and Bromodomain PHD transcription factor bromodomain(BPTF BRD)are the same subfamily proteins,both of which are highly conserved in sequence and binding pockets.Challenges remain in the development of small molecules to inhibit one of the two bromodomains(BRDs),in view of each subtype may possess unique physiological and pathological functions.There is still a lack of effective selective inhibitors of CECR2 BRD,which makes it difficult to fully understand the pathogenesis of CECR2-BRD in diseases,especially cancers.Herein,we report our efforts to discover a series of highly selective CECR2 BRD inhibitors over BPTF BRD based on TP-248.Structure-based molecular optimization led to the discovery of DC-CEi-26,whose IC_(50) for CECR2 BRD was 96.7±14.9 nmol/L and selectivity was up to 590×over BPTF BRD.DC-CEi-26 showed weak potencies for other classic BRDs in different subfamily,which may serve as a chemical probe for CECR2 BRD biological research.展开更多
Gastrointestinal(GI)cancers,including colorectal cancer,pancreatic cancer,liver cancer and gastric cancer,are severe social burdens due to high incidence and mortality rates.Bromodomain and extra-terminal(BET)proteins...Gastrointestinal(GI)cancers,including colorectal cancer,pancreatic cancer,liver cancer and gastric cancer,are severe social burdens due to high incidence and mortality rates.Bromodomain and extra-terminal(BET)proteins are epigenetic readers consisting of four conserved members(BRD2,BRD3,BRD4 and BRDT).BET family perform pivotal roles in tumorigenesis through transcriptional regulation,thereby emerging as potential therapeutic targets.BET inhibitors,disrupting the interaction between BET proteins and acetylated lysines,have been reported to suppress tumor initiation and progression in most of GI cancers.In this review,we will demonstrate how BET proteins participate in the GI cancers progression and highlight the therapeutic potential of targeting BET proteins for GI cancers treatment.展开更多
Lysine acetylation is one of the most prevalent and important posttranslational modifications(PTMs) in proteins. The process can be recognized by bromodomains(BRDs), which are a class of proteininteraction modules inv...Lysine acetylation is one of the most prevalent and important posttranslational modifications(PTMs) in proteins. The process can be recognized by bromodomains(BRDs), which are a class of proteininteraction modules involved in chromatin remodeling and transcriptional activation. The development of BRD fluorescent probes will be useful for monitoring the activity of BRDs in living cells as well as aiding inhibitor development. Herein we designed a peptide-based probe based on the proximity-induced protein conjugation reaction. The peptide-based probe is capable of covalently and selectively reacting with the unique cysteine residue in the bromodomain through proximity effect. Our experimental data showed that the probe displayed noticeable fluorescence response upon addition of BRD4(1). In-gel fluorescence scanning demonstrated that BRD4(1) can be covalently labelled by the probe. Moreover, the probe was shown to selectively detect BRD4(1) over other proteins. We envision that the probe developed in this study will provide a useful tool to further investigate the biological roles of BRDs.展开更多
基金This work was supported by grants from the National Natural Science Foundation of China(82103183,82102803,82272849)the Natural Science Foundation of Hunan Province(2022JJ40767,2021JJ40976)+1 种基金the Natural Science Fund for Outstanding Youths in Hunan Province(2023JJ20093)the National Key Research and Development Program(2022YFC2504700).
文摘Dear Editor,Ferroptosis,an iron-dependent form of cell death driven by overwhelming lipid peroxidation,represents a vulnerability in cancers,and therapeutic strategies to further potentiate ferroptosis hold great potential for melanoma treatment.
基金supported by grants from National Institute of Health(Grant Nos.R33AI116180,R01DE025447,and R01GM117838)
文摘Proteins usually associate with other molecules physically to execute their functions.Identifying these interactions is important for the functional analysis of proteins.Previously,we reported the parallel analysis of translated ORFs(PLATO)to couple ribosome display of full-length ORFs with affinity enrichment of mRNA/protein/ribosome complexes for the “bait”molecules,followed by the deep sequencing analysis of mRNA.However,the sample processing,from extraction of precipitated mRNA to generation of DNA libraries,includes numerous steps,which is tedious and may cause the loss of materials.Barcoded PLATO(PLATO-BC),an improved platform was further developed to test its application for protein interaction discovery.In this report,we tested the antisera-antigen interaction using serum samples from patients with inclusion body myositis(IBM).Tripartite motif containing 21(TRIM21)was identified as a potentially new IBM autoantigen.We also expanded the application of PLATO-BC to identify protein interactions for JQ1,single ubiquitin peptide,and NS5 protein of Zika virus.From PLATO-BC analyses,we identified new protein interactions for these “bait”molecules.We demonstrate that Ewing sarcoma breakpoint region 1(EWSR1)binds to JQ1 and their interactions may interrupt the EWSR1 association with acetylated histone H4.RIO kinase 3(RIOK3),a newly identified ubiquitin-binding protein,is preferentially associated with K63-ubiquitin chain.We also find that Zika NS5 protein interacts with two previously unreported host proteins,par-3 family cell polarity regulator(PARD3)and chromosome 19 open reading frame 53(C19orf53),whose attenuated expression benefits the replication of Zika virus.These results further demonstrate that PLATO-BC is capable of identifying novel protein interactions for various types of “bait”molecules.
基金Supported by the National Natural Science Foundation of China,No.81871317.
文摘BACKGROUND The overexpression of the MYC gene plays an important role in the occurrence,development and evolution of colorectal cancer(CRC).Bromodomain and extraterminal domain(BET)inhibitors can decrease the function BET by recognizing acetylated lysine residues,thereby downregulating the expression of MYC.AIM To investigate the inhibitory effect and mechanism of a BET inhibitor on CRC cells.METHODS The effect of the BET inhibitor JAB-8263 on the proliferation of various CRC cell lines was studied by CellTiter-Glo method and colony formation assay.The effect of JAB-8263 on the cell cycle and apoptosis of CRC cells was studied by propidium iodide staining and Annexin V/propidium iodide flow assay,respectively.The effect of JAB-8263 on the expression of c-MYC,p21 and p16 in CRC cells was detected by western blotting assay.The anti-tumor effect of JAB-8263 on CRC cells in vivo and evaluation of the safety of the compound was predicted by constructing a CRC cell animal tumor model.RESULTS JAB-8263 dose-dependently suppressed CRC cell proliferation and colony formation in vitro.The MYC signaling pathway was dose-dependently inhibited by JAB-8263 in human CRC cell lines.JAB-8263 dose-dependently induced cell cycle arrest and apoptosis in the MC38 cell line.SW837 xenograft model was treated with JAB-8263(0.3 mg/kg for 29 d),and the average tumor volume was significantly decreased compared to the vehicle control group(P<0.001).The MC38 syngeneic murine model was treated with JAB-8263(0.2 mg/kg for 29 d),and the average tumor volume was significantly decreased compared to the vehicle control group(P=0.003).CONCLUSION BET could be a potential effective drug target for suppressing CRC growth,and the BET inhibitor JAB-8263 can effectively suppress c-MYC expression and exert anti-tumor activity in CRC models.
基金supported by the National Natural Science Foundation of China to C.L.(32000380 and 31870289)Guangdong Basic and Applied Basic Research Foundation to C.L.(2021A1515011286)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University to C.L(18lgzd12).
文摘Switch defective/sucrose non-fermentable(SWI/SNF)chromatin remodeling complexes are multi-subunit machines that play vital roles in the regulation of chromatin structure and gene expression.However,the mechanisms by which SWI/SNF complexes recognize their target loci in plants are not fully understood.Here,we show that the Arabidopsis thaliana bromodomain-containing proteins BRD1,BRD2,and BRD13 are core subunits of SWI/SNF complexes and critical for SWI/SNF genomic targeting.These three BRDs interact directly with multiple SWI/SNF subunits,including the BRAHMA(BRM)catalytic subunit.Phenotypic and transcriptomic analyses of the brd1 brd2 brd13 triple mutant revealed that these BRDs act largely redundantly to control gene expression and developmental processes that are also regulated by BRM.Genome-wide occupancy profiling demonstrated that these three BRDs extensively colocalize with BRM on chromatin.Simultaneous loss of function of three BRD genes results in reduced BRM protein levels and decreased occupancy of BRM on chromatin across the genome.Furthermore,we demonstrated that the bromodomains of BRDs are essential for genomic targeting of the BRD subunits of SWI/SNF complexes to their target sites.Collectively,these results demonstrate that BRD1,BRD2,and BRD13 are core subunits of SWI/SNF complexes and reveal their biological roles in facilitating genomic targeting of BRM-containing SWI/SNF complexes in plants.
文摘The Polybromo （PB） protein functions as a key component of the human PBAF chromatin remodeling complex in regulation of gene transcription. PB is made up of modular domains including six bromodomains that are known as acetyl-lysine binding domains. However, histone-binding specificity of the bromodomains of PB has remained elusive. In this study, we report biochemical characterization of all six PB bromodomains＇ binding to a suite of lysine-acetylated peptides derived from known acetylation sites on human core histones. We demonstrate that bromodomain 2 of PB preferentially recognizes acetylated lysine 14 of histone H3 （H3K14ac）, a post-translational mark known for gene transcriptional activation. We further describe the molecular basis of the selective H3K14ac recognition of bromodomain 2 by solving the protein structures in both the free and bound forms using X-ray crystallography and NMR, respectively.
基金Supported by the open project of the State Key Laboratory of Crop Stress Biology for Arid Areas,Northwest A&F University,China(CSBAA2016001).
文摘FgGCN5,a GCN5 homolog in Fusarium graminearum,plays a critical role in hyphal vegetative growth,asexual and sexual reproduction,deoxynivalenol(DON)biosynthesis and plant infection.For nuclear localized GCN5,four conserved sequence motifs(I-IV)are presented in the catalytic domain and a bromodomain in the carboxy-terminus.As a lysine acetyltransferase,conserved negatively charged residues are present to neutralize the protons from lysine substrates.However,the role of conserved motifs/domains and residues in FgGCN5 are unclear.Here,we generated deletion mutant strains for each the conserved motifs/domains and a glutamate residue 130(E130)replacement mutant.Deletion of each conserved motif in the catalytic domain and replacement of E130 site resulted in manifold defects in hyphae growth,asexual and sexual development,DON biosynthesis,and plant infection.Phenotypic defects in the mutant strains were similar to deletion mutants.The deletion of the bromodomain led a significant reduction in DON production and virulence,with no effects on hyphae growth,asexual or sexual reproduction.FgGCN5 was further found to localize to the nucleus in conidia and hyphae cells.In conclusion,FgGCN5 encodes a nuclear localized acetyltransferase.The conserved motifs in the catalytic domain and E130 are essential for correct functions of the gene.The conserved bromodomain is impotant for DON production and pathogen virulence.This was the first report to identify the functions of conserved motifs/domains in FgGCN5,which will contribute to our understanding of the mechanism(s)by which FgGCN5 regulates F.graminearum.
文摘组蛋白N末端赖氨酸的乙酰化在转录调控中有重要作用。多种含Bromodomain的蛋白可以与乙酰化赖氨酸结合并招募其它染色质因子来协同调控基因转录,这一过程与人体很多疾病的产生和发展密切相关。本文中对近年来Bromodomain-containing protein 9(BRD9)选择性的小分子抑制剂的研究进展进行了总结。
基金the Science and Technology Commission of Shanghai Municipality(Y811298033 to Q.L.,and 19XD1404700 to C.L.)the scientific research innovation program“Xiyuanjiang River Scholarship”of the College of Life Sciences,Fujian Normal University+3 种基金the State Key Laboratory of Drug Research(SIMM2105KF-07toH.L.)Fujian Provincial Natural Science Foundation(2021J01203 to H.L.)the Natural Science Foundation of Fujian Province(2019J05073 to J.L.)the Joint Funds forthe Innovation of Science and Technology of Fujian Province(2018Y9071 to J.L.).
文摘Cat's eye syndrome chromosome candidate 2 bromodomain(CECR2 BRD)and Bromodomain PHD transcription factor bromodomain(BPTF BRD)are the same subfamily proteins,both of which are highly conserved in sequence and binding pockets.Challenges remain in the development of small molecules to inhibit one of the two bromodomains(BRDs),in view of each subtype may possess unique physiological and pathological functions.There is still a lack of effective selective inhibitors of CECR2 BRD,which makes it difficult to fully understand the pathogenesis of CECR2-BRD in diseases,especially cancers.Herein,we report our efforts to discover a series of highly selective CECR2 BRD inhibitors over BPTF BRD based on TP-248.Structure-based molecular optimization led to the discovery of DC-CEi-26,whose IC_(50) for CECR2 BRD was 96.7±14.9 nmol/L and selectivity was up to 590×over BPTF BRD.DC-CEi-26 showed weak potencies for other classic BRDs in different subfamily,which may serve as a chemical probe for CECR2 BRD biological research.
基金Fellowship of the China Postdoctoral Science Foundation,No.2020M682594,and No.2021T140748.
文摘Gastrointestinal(GI)cancers,including colorectal cancer,pancreatic cancer,liver cancer and gastric cancer,are severe social burdens due to high incidence and mortality rates.Bromodomain and extra-terminal(BET)proteins are epigenetic readers consisting of four conserved members(BRD2,BRD3,BRD4 and BRDT).BET family perform pivotal roles in tumorigenesis through transcriptional regulation,thereby emerging as potential therapeutic targets.BET inhibitors,disrupting the interaction between BET proteins and acetylated lysines,have been reported to suppress tumor initiation and progression in most of GI cancers.In this review,we will demonstrate how BET proteins participate in the GI cancers progression and highlight the therapeutic potential of targeting BET proteins for GI cancers treatment.
基金the financial support from the National Natural Science Foundation of China (No. 21572190)the Hong Kong Early Career Scheme Grant (No. 21300714)the City University of Hong Kong Grant (No. 9667147)
文摘Lysine acetylation is one of the most prevalent and important posttranslational modifications(PTMs) in proteins. The process can be recognized by bromodomains(BRDs), which are a class of proteininteraction modules involved in chromatin remodeling and transcriptional activation. The development of BRD fluorescent probes will be useful for monitoring the activity of BRDs in living cells as well as aiding inhibitor development. Herein we designed a peptide-based probe based on the proximity-induced protein conjugation reaction. The peptide-based probe is capable of covalently and selectively reacting with the unique cysteine residue in the bromodomain through proximity effect. Our experimental data showed that the probe displayed noticeable fluorescence response upon addition of BRD4(1). In-gel fluorescence scanning demonstrated that BRD4(1) can be covalently labelled by the probe. Moreover, the probe was shown to selectively detect BRD4(1) over other proteins. We envision that the probe developed in this study will provide a useful tool to further investigate the biological roles of BRDs.
