Protein labeling by using a protein tag and tag-specific fluorescent probes is increasingly becoming a useful technique for the real-time imaging of proteins in living cells. SNAP-tag as one of the most prominent fusi...Protein labeling by using a protein tag and tag-specific fluorescent probes is increasingly becoming a useful technique for the real-time imaging of proteins in living cells. SNAP-tag as one of the most prominent fusion tags has been widely used and already commercially available. Recently, various fluorogenic probes for SNAP-tag based protein labeling were reported. Owing to turn-on fluorescence response, fluorogenic probes for SNAP-tag minimize the fluorescence background caused by unreacted or nonspecifically bound probes and allow for direct imaging in living cells without wash-out steps. Thus,real-time analysis of protein localization, dynamics and interactions has been made possible by SNAP-tag fluorogenic probes. In this review,we describe the design strategies of fluorogenic probes for SNAP-tag and their applications in cellular protein labeling.展开更多
Imaging dynamics of membrane proteins of live cells in a wash-free and real-time manner has been a challenging task. Herein, we report unprecedented applications of malachite green(MG), an organic dye widely used in p...Imaging dynamics of membrane proteins of live cells in a wash-free and real-time manner has been a challenging task. Herein, we report unprecedented applications of malachite green(MG), an organic dye widely used in pigment industry, as a switchable fluorophore to monitor membrane enzymes or noncatalytic proteins in live cells. Conformationally flexible MG is non-fluorescent in aqueous solution, yet covalent binding with endogenous proteins of cells significantly enhances its fluorescence at 670 nm by restricting flexibility of dye. Integrating a phosphate-caged quinone methide precursor with MG yielded a covalent labeling fluorogenic probe, allowing real-time imaging of membrane alkaline phosphatase(ALP,a model catalytic protein) activity in live cells with over 100-fold enhancement of fluorescence intensity.Moreover, MG is also applicable to image non-catalytic protein by conjugation with protein-specific ligand. A fluorogenic probe consisted of c-RGDf K peptide and MG proved to be compatible with wash-free and real-time visualization of non-catalytic integrin α_(v)β_(3) in live cells with high contrast.展开更多
Monoamine oxidase is flavoenzymes, widely distributed in mammals. It is well recognized that MAOs serve an important role in metabolism that they have close relationship with health .Along with the discoveries between...Monoamine oxidase is flavoenzymes, widely distributed in mammals. It is well recognized that MAOs serve an important role in metabolism that they have close relationship with health .Along with the discoveries between MAOs and neurotic disease, more and more studies have been jumped in .In this paper, we design a new probe for assaying the activities of MAOs. The results showed that the probe [7-（3-aminopropoxy）coumarin] is simple, effective and sensitive for MAOB.展开更多
Hepatic ischemia-reperfusion injury(HIRI)is the cause of postoperative hepatic dysfunction and failure,and even death.As an important biological effector molecule,hydrogen sulfide(H_(2)S)of mitochondria as a gasotrans...Hepatic ischemia-reperfusion injury(HIRI)is the cause of postoperative hepatic dysfunction and failure,and even death.As an important biological effector molecule,hydrogen sulfide(H_(2)S)of mitochondria as a gasotransmitter that is usually used to protect against acute HIRI injury.However,the exact relationship between HIRI and mitochondrial H_(2)S remains tangled due to the lack of an effective analytical method.Herein,we have fabricated a mitochondria-targeted H_(2)S-activatable fluorogenic probe(Mito-GW)to explore the stability of mitochondrial H_(2)S and track the changes of mitochondrial H_(2)S during the HIRI.By virtue of pyridinium electropositivity and its amphiphilicity,Mito-GW could accumulate in mitochondria.It goes through an analyte-prompted immolation when reacts with H_(2)S,resulting in the releasing of the fluorophore(GW).Therefore,the extent of Mito-GW conversion to GW can be used to evaluate the changes of mitochondrial H_(2)S level in living cells and tissues.As proof-of-principle,we have used MitoGW to demonstrate the mitochondria H_(2)S-levels increase and then decrease during HIRI in vitro and in vivo.Our research highlights the tremendous potential of Mito-GW as a mitochondrial H_(2)S fluorogenic probe in elucidating the pathogenesis of HIRI,providing a powerful tool for promoting future research on hepatology.展开更多
Porcine lipoprotein lipase （LPL） cDNA was cloned as the standard for real-time quantifying LPL mRNA and the TaqMan-fluorescence quantitative PCR assay for detection was established. The total RNA extracted from Long...Porcine lipoprotein lipase （LPL） cDNA was cloned as the standard for real-time quantifying LPL mRNA and the TaqMan-fluorescence quantitative PCR assay for detection was established. The total RNA extracted from Longissimus dorsi of porcine was reverse-transcribed to cDNA. LPL cDNA was ligated with pGM-T vector and transformed into Escherichia coli TOP10. Plasmid DNA extracted from positive clones was verified by PCR amplification and sequenced. LPL was amplified by real-time fluorescence quantitative PCR from the plasmid DNA. The concentration of DNA template purified was detected by analyzing absorbance in 260 nm and then the combined plasmid was diluted to series as standard for fluorescence quantitative PCR （FQ-PCR）. The method of LPL mRNA real-time PCR was well established, which detected as low as 103 with the linear range 10^3 to 10^10 copies. The standard curves showed high correlations （R2 = 0.9871）. A series of standards for real-time PCR analysis have been constructed successfially, and real-time TaqMan-fluorescence quantitative RT-PCR is reliable to quantitatively evaluate FQ-PCR mRNA in L. dorsi of porcine.展开更多
Protein self-labeling tags achieve selective fusion and labeling of target proteins through genetic coding technology,but require exogenous fluorescent probes with fluorogenicity for protein tag binding to have the pe...Protein self-labeling tags achieve selective fusion and labeling of target proteins through genetic coding technology,but require exogenous fluorescent probes with fluorogenicity for protein tag binding to have the performance of wash-free fluorescence imaging in live cells.In this paper,we reported a fluorogenic probe 1 capable of ratiometric fluorescence recognition of SNAP-tag proteins.In this probe,the O6-benzylguanine derivative of 3-hydroxy-1,8-naphthalimide underwent a selective covalent linkage reaction with SNAP-tag protein.The hydroxyl group on the naphthalimide fluorophore formed a hydrogen bond with the functional group near the protein cavity.The excited state proton transfer occurred after illumination,to obtain the ratio fluorescence signal from blue emission to red emission,realizing the wash-free fluorescence imaging of the target proteins.展开更多
H2S is an essential gas signal molecule in cells,and viscosity is a key internal environmental parameter.Recent studies have shown that H_(2)S acts as a cytoarchitecture agent and gas transmitter in many tissues,e.g.,...H2S is an essential gas signal molecule in cells,and viscosity is a key internal environmental parameter.Recent studies have shown that H_(2)S acts as a cytoarchitecture agent and gas transmitter in many tissues,e.g.,as a regulator of neuroendocrine in the brain for mediating vascular tone in blood vessels.Mitochondrial viscosity is an important parameter for judging whether mitochondrial function is normal.It has been reported that oxidative stress and mitochondrial dysfunction are connected with Parkinson’s disease(PD),and the protective role of H_(2)S in PD models has been extensively demonstrated.Herein,Mito-HS,a new two-photon fluorescent probe was demonstrated to detect cross-talk between the two channels of mitochondrial viscosity and H_(2)S content.Moreover,this probe could detect the relative amount of and changes in mitochondrial H2S in situ due to the reduced mitochondrial targeting ability after reaction with H_(2)S.The results show that H2S in mitochondria is inversely related to viscosity.The PD model has a lower H2S in mitochondria and a higher mitochondrial viscosity than did the normal.This result is important for our deep understanding of PD and its causes.展开更多
Monitoring mitochondrial derived copper（Ⅱ） in live cells is highly demanded, but accurately detecting is unmet due to the interference with cytoplasmic copper（Ⅱ）. Herein, we have reported the design,synthesis an...Monitoring mitochondrial derived copper（Ⅱ） in live cells is highly demanded, but accurately detecting is unmet due to the interference with cytoplasmic copper（Ⅱ）. Herein, we have reported the design,synthesis and characterization of photocontrollable fluorogenic probe, MCu-3, which is equipped with a photo-labile group（nitrobenzyl group） and mitochondria targeting unit（triphenylphosphonium salt）.This novel probe showed an intense fluorescence enhancement in response to copper（Ⅱ） without interference from other metal cations in the biological condition（p H 6–9）. The detection limit is 1.7 ×10^（-7） mol/L in HEPES buffer. The confocal fluorescence imaging results demonstrated MCu-3 can visualize mitochondrial copper（Ⅱ） in live mammalian cells. The clear advantage of our photocontrollable method is successful to avoid the influence of cytoplasmic copper（Ⅱ） during mitochondria specific detection.展开更多
Herein we presented a general strategy for in situ assembly of intramolecular charge-transfer(ICT)-based light-up fluorophores via bioorthogonal Suzuki-Miyaura cross-coupling reaction.By introducing iodo group at the ...Herein we presented a general strategy for in situ assembly of intramolecular charge-transfer(ICT)-based light-up fluorophores via bioorthogonal Suzuki-Miyaura cross-coupling reaction.By introducing iodo group at the appropriate position,five fluorophores with different scaffolds including naphthalimide,coumarin,naphthalene sulfonate,nitrobenzoxadiazole,and acetonaphthone,were designed as bioorthogonal multicolor fluorogenic probes,which could produce significant fluorescence enhancement and high fluorescence quantum yield after Suzuki-Miyaura reaction with aryl boronic acid or boronate.Manipulating the substituents andπscaffold in the fluorophores allows fine-tuning of their photophysical properties.With this strategy,we succeeded in peptide conjugation,no-wash fluorogenic protein labeling,and mitochondria-selective bioorthogonal imaging in live cells.展开更多
The application of a new fluorogenic probe-based PCR assay (PCR duplex scorpion primer assay) to the detection of Hepatitis B virus (HBV) DNA in human sera was described. Duplex scorpion primer is a modified variant o...The application of a new fluorogenic probe-based PCR assay (PCR duplex scorpion primer assay) to the detection of Hepatitis B virus (HBV) DNA in human sera was described. Duplex scorpion primer is a modified variant of duplex Amplifluor, and the incorporation of a PCR stopper between probe and primer sequences improve the detection specificity and sensitivity. Combined with PCR amplification, this probe can give unambiguous positive results for the reactions initiated with more than 20 HBV molecules. In addition, the particular unimolecular probing mechanism of this probe makes the use of short target-specific probe sequence possible, which will render this probe applicable in some specific systems.展开更多
基金supports from the National Natural Science Foundation of China (Nos. 21422606 and 21502189)Dalian Cultivation Fund for Distinguished Young Scholars (Nos. 2014J11JH130 and 2015J12JH205)
文摘Protein labeling by using a protein tag and tag-specific fluorescent probes is increasingly becoming a useful technique for the real-time imaging of proteins in living cells. SNAP-tag as one of the most prominent fusion tags has been widely used and already commercially available. Recently, various fluorogenic probes for SNAP-tag based protein labeling were reported. Owing to turn-on fluorescence response, fluorogenic probes for SNAP-tag minimize the fluorescence background caused by unreacted or nonspecifically bound probes and allow for direct imaging in living cells without wash-out steps. Thus,real-time analysis of protein localization, dynamics and interactions has been made possible by SNAP-tag fluorogenic probes. In this review,we describe the design strategies of fluorogenic probes for SNAP-tag and their applications in cellular protein labeling.
基金financially supported by the National Natural Science Foundation of China (No. 22077031)the Research Program of State Key Laboratory of Bioreactor Engineeringthe Fundamental Research Funds for the Central Universities。
文摘Imaging dynamics of membrane proteins of live cells in a wash-free and real-time manner has been a challenging task. Herein, we report unprecedented applications of malachite green(MG), an organic dye widely used in pigment industry, as a switchable fluorophore to monitor membrane enzymes or noncatalytic proteins in live cells. Conformationally flexible MG is non-fluorescent in aqueous solution, yet covalent binding with endogenous proteins of cells significantly enhances its fluorescence at 670 nm by restricting flexibility of dye. Integrating a phosphate-caged quinone methide precursor with MG yielded a covalent labeling fluorogenic probe, allowing real-time imaging of membrane alkaline phosphatase(ALP,a model catalytic protein) activity in live cells with over 100-fold enhancement of fluorescence intensity.Moreover, MG is also applicable to image non-catalytic protein by conjugation with protein-specific ligand. A fluorogenic probe consisted of c-RGDf K peptide and MG proved to be compatible with wash-free and real-time visualization of non-catalytic integrin α_(v)β_(3) in live cells with high contrast.
基金the project sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars Fund,Zhejiang Province(No.Z01105002)Returned Overseas Chinese Scholars Fund.
文摘Monoamine oxidase is flavoenzymes, widely distributed in mammals. It is well recognized that MAOs serve an important role in metabolism that they have close relationship with health .Along with the discoveries between MAOs and neurotic disease, more and more studies have been jumped in .In this paper, we design a new probe for assaying the activities of MAOs. The results showed that the probe [7-（3-aminopropoxy）coumarin] is simple, effective and sensitive for MAOB.
基金financially supported by the National Natural Science Foundation of China(Nos.22077101,22004099)the Joint Research Funds of Department of Science&Technology of Shaanxi Province and Northwestern Polytechnical University(Nos.2020GXLH-Z-008,2020GXLH-Z-021,2020GXLH-Z-023)+4 种基金Natural Science Foundation of Shaanxi Province(No.2022JM-130)The Natural Science Foundation of Ningbo(Nos.202003N4049,202003N4065)the Open Project Program of Wuhan National Laboratory for Optoelectronics(Nos.2020WNLOKF023,2022WNLOKF009)Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(No.CX2022034)Innovation Capability Support Program of Shaanxi(No.2023-CX-PT-23)。
文摘Hepatic ischemia-reperfusion injury(HIRI)is the cause of postoperative hepatic dysfunction and failure,and even death.As an important biological effector molecule,hydrogen sulfide(H_(2)S)of mitochondria as a gasotransmitter that is usually used to protect against acute HIRI injury.However,the exact relationship between HIRI and mitochondrial H_(2)S remains tangled due to the lack of an effective analytical method.Herein,we have fabricated a mitochondria-targeted H_(2)S-activatable fluorogenic probe(Mito-GW)to explore the stability of mitochondrial H_(2)S and track the changes of mitochondrial H_(2)S during the HIRI.By virtue of pyridinium electropositivity and its amphiphilicity,Mito-GW could accumulate in mitochondria.It goes through an analyte-prompted immolation when reacts with H_(2)S,resulting in the releasing of the fluorophore(GW).Therefore,the extent of Mito-GW conversion to GW can be used to evaluate the changes of mitochondrial H_(2)S level in living cells and tissues.As proof-of-principle,we have used MitoGW to demonstrate the mitochondria H_(2)S-levels increase and then decrease during HIRI in vitro and in vivo.Our research highlights the tremendous potential of Mito-GW as a mitochondrial H_(2)S fluorogenic probe in elucidating the pathogenesis of HIRI,providing a powerful tool for promoting future research on hepatology.
基金support provided by the 973 Program of China (2004CB117500)
文摘Porcine lipoprotein lipase （LPL） cDNA was cloned as the standard for real-time quantifying LPL mRNA and the TaqMan-fluorescence quantitative PCR assay for detection was established. The total RNA extracted from Longissimus dorsi of porcine was reverse-transcribed to cDNA. LPL cDNA was ligated with pGM-T vector and transformed into Escherichia coli TOP10. Plasmid DNA extracted from positive clones was verified by PCR amplification and sequenced. LPL was amplified by real-time fluorescence quantitative PCR from the plasmid DNA. The concentration of DNA template purified was detected by analyzing absorbance in 260 nm and then the combined plasmid was diluted to series as standard for fluorescence quantitative PCR （FQ-PCR）. The method of LPL mRNA real-time PCR was well established, which detected as low as 103 with the linear range 10^3 to 10^10 copies. The standard curves showed high correlations （R2 = 0.9871）. A series of standards for real-time PCR analysis have been constructed successfially, and real-time TaqMan-fluorescence quantitative RT-PCR is reliable to quantitatively evaluate FQ-PCR mRNA in L. dorsi of porcine.
基金supported by the National Natural Science Foundation of China(Nos.22225806,22078314 and 22278394)Dalian Institute of Chemical Physics(Nos.DICPI202227 and DICPI202142)。
文摘Protein self-labeling tags achieve selective fusion and labeling of target proteins through genetic coding technology,but require exogenous fluorescent probes with fluorogenicity for protein tag binding to have the performance of wash-free fluorescence imaging in live cells.In this paper,we reported a fluorogenic probe 1 capable of ratiometric fluorescence recognition of SNAP-tag proteins.In this probe,the O6-benzylguanine derivative of 3-hydroxy-1,8-naphthalimide underwent a selective covalent linkage reaction with SNAP-tag protein.The hydroxyl group on the naphthalimide fluorophore formed a hydrogen bond with the functional group near the protein cavity.The excited state proton transfer occurred after illumination,to obtain the ratio fluorescence signal from blue emission to red emission,realizing the wash-free fluorescence imaging of the target proteins.
基金the National Natural Science Foundation of China(Nos.81672508,21675085)Jiangsu Provincial Foundation for Distinguished Young Scholars(Nos.BK20170041,BK20170042)+2 种基金Natural Science Foundation of Shaanxi Province(No.2019JM-016)China-Sweden Joint Mobility Project(No.51811530018)Fundamental Research Funds for the Central Universities。
文摘H2S is an essential gas signal molecule in cells,and viscosity is a key internal environmental parameter.Recent studies have shown that H_(2)S acts as a cytoarchitecture agent and gas transmitter in many tissues,e.g.,as a regulator of neuroendocrine in the brain for mediating vascular tone in blood vessels.Mitochondrial viscosity is an important parameter for judging whether mitochondrial function is normal.It has been reported that oxidative stress and mitochondrial dysfunction are connected with Parkinson’s disease(PD),and the protective role of H_(2)S in PD models has been extensively demonstrated.Herein,Mito-HS,a new two-photon fluorescent probe was demonstrated to detect cross-talk between the two channels of mitochondrial viscosity and H_(2)S content.Moreover,this probe could detect the relative amount of and changes in mitochondrial H2S in situ due to the reduced mitochondrial targeting ability after reaction with H_(2)S.The results show that H2S in mitochondria is inversely related to viscosity.The PD model has a lower H2S in mitochondria and a higher mitochondrial viscosity than did the normal.This result is important for our deep understanding of PD and its causes.
基金supported by the National Natural Science Foundation of China (Nos. 81672508, 61505076)Natural Science Foundation of Jiangsu Province (No. BK20140951)+1 种基金Key University Science Research Project of Jiangsu Province (No. 16KJA180004)SICAM Fellowship & Scholarship by Jiangsu National Synergetic Innovation Center for Advanced Materials
文摘Monitoring mitochondrial derived copper（Ⅱ） in live cells is highly demanded, but accurately detecting is unmet due to the interference with cytoplasmic copper（Ⅱ）. Herein, we have reported the design,synthesis and characterization of photocontrollable fluorogenic probe, MCu-3, which is equipped with a photo-labile group（nitrobenzyl group） and mitochondria targeting unit（triphenylphosphonium salt）.This novel probe showed an intense fluorescence enhancement in response to copper（Ⅱ） without interference from other metal cations in the biological condition（p H 6–9）. The detection limit is 1.7 ×10^（-7） mol/L in HEPES buffer. The confocal fluorescence imaging results demonstrated MCu-3 can visualize mitochondrial copper（Ⅱ） in live mammalian cells. The clear advantage of our photocontrollable method is successful to avoid the influence of cytoplasmic copper（Ⅱ） during mitochondria specific detection.
基金supported by the Beijing Nova Program(No.Z201100006820049)the National Natural Science Foundation of China(No.21907109)the CAMS Innovation Fund for Graduate Students(No.2019–1007–03)
文摘Herein we presented a general strategy for in situ assembly of intramolecular charge-transfer(ICT)-based light-up fluorophores via bioorthogonal Suzuki-Miyaura cross-coupling reaction.By introducing iodo group at the appropriate position,five fluorophores with different scaffolds including naphthalimide,coumarin,naphthalene sulfonate,nitrobenzoxadiazole,and acetonaphthone,were designed as bioorthogonal multicolor fluorogenic probes,which could produce significant fluorescence enhancement and high fluorescence quantum yield after Suzuki-Miyaura reaction with aryl boronic acid or boronate.Manipulating the substituents andπscaffold in the fluorophores allows fine-tuning of their photophysical properties.With this strategy,we succeeded in peptide conjugation,no-wash fluorogenic protein labeling,and mitochondria-selective bioorthogonal imaging in live cells.
基金the National Natural Science Foundation of China (No. 20075012) and the Outstanding Scholar Program of Nankai University.
文摘The application of a new fluorogenic probe-based PCR assay (PCR duplex scorpion primer assay) to the detection of Hepatitis B virus (HBV) DNA in human sera was described. Duplex scorpion primer is a modified variant of duplex Amplifluor, and the incorporation of a PCR stopper between probe and primer sequences improve the detection specificity and sensitivity. Combined with PCR amplification, this probe can give unambiguous positive results for the reactions initiated with more than 20 HBV molecules. In addition, the particular unimolecular probing mechanism of this probe makes the use of short target-specific probe sequence possible, which will render this probe applicable in some specific systems.
