Mitochondria are crucial sites for protein quality control within cells.When mitochondrial stress is triggered by protein misfolding,it can accelerate abnormal protein aggregation,potentially inducing various diseases...Mitochondria are crucial sites for protein quality control within cells.When mitochondrial stress is triggered by protein misfolding,it can accelerate abnormal protein aggregation,potentially inducing various diseases.This study developed a cascade-responsive sensor,named AggHX,to monitor the microenvironment of protein aggregation induced by zinc(II)ions and the accompanying mitochondrial dysfunction.The AggHX consists of two key components:(1)A Zn^(2+) þrecognition group for triggering a fluorescent enhance response,and(2)a near-infrared BODIPY scaffold that detects viscosity changes in cell aggregation via HaloTag.This sensor's mechanism of action is elucidated through photochemical and biochemical characterizations.To further investigate the relationship between protein aggregation and mitochondrial homeostasis,we employ fluorescence lifetime imaging microscopy to assess viscosity changes in protein aggregates under intracellular Zn2þstress.This research provides insights into the dynamic behavior and spatial distribution of protein aggregates and mitochondria,contributing to a deeper understanding of their physiological roles in cellular processes and potential implications in disease pathology.展开更多
Changes in cellular viscosity are associated with various physiological processes and pathological conditions.To study these cellular processes and functions,highly sensitive fluorescent probes that detect subtle chan...Changes in cellular viscosity are associated with various physiological processes and pathological conditions.To study these cellular processes and functions,highly sensitive fluorescent probes that detect subtle changes in viscosity are urgently needed but remain lacking.In this study,we present a series of viscosity-responsive near-infrared(NIR)fluorescent probes based on styrene-coated boron dipyrromethene(BODIPY).The probe modified with dimethylaminostyrene and piperazine at the two terminals of the BODIPY scaffold showed extremely high viscosity sensitivity values(x,around 1.54),with excellent performance for detecting viscosity below 20 c P.This outstanding property is attributed to the synergistic effects of multiple rotatable bonds and hydrogen-bond interactions.Additionally,this probe has been successfully deployed to monitor viscosity changes in various cellular compartments(i.e.,cytoplasm)and processes(such as during autophagy).This work provides a rational molecular design strategy to construct fluorescent probes with high viscosity sensitivity for exploring cell functions.展开更多
Molecular rotor-based fluorophores(RBFs)activate fluorescence upon increase of micro-viscosity,thus bearing a broad application promise in many fields.However,it remains a challenge to control how fluorescence of RBFs...Molecular rotor-based fluorophores(RBFs)activate fluorescence upon increase of micro-viscosity,thus bearing a broad application promise in many fields.However,it remains a challenge to control how fluorescence of RBFs responds to viscosity changes.Herein,we demonstrate that the formation and regulation of intramolecular hydrogen bonds in the excited state of RBFs could modulate their rotational barrier,leading to a rational control of how their fluorescence can be activated by micro-viscosity.Based on this strategy,a series of RBFs were developed based on 4-hydroxybenzylidene-imidazolinone(HBI)that span a wide range of viscosity sensitivity.Combined with the AggTag method that we previously reported,the varying viscosity sensitivity and emission spectra of these probes enabled a dualcolor imaging strategy that detects both protein oligomers and aggregates during the multistep aggregation process of proteins in live cells.In summary,our work indicates that installing intracellular excited state hydrogen bonds to RBFs allows for a rational control of rotational barrier,thus allow for a fine tune of their viscosity sensitivity.Beyond RBFs,we envision similar strategies can be applied to control the fluorogenic behavior of a large group of fluorophores whose emission is dependent on excited state rotational motion,including aggregation-induced emission fluorophores.展开更多
基金support from the Qinglan Project of Jiangsu Province of China,National Natural Science Foundation of China(Grant No.22007048)the Natural Science Foundation of Jiangsu Basic Research Program(BK20221324).
文摘Mitochondria are crucial sites for protein quality control within cells.When mitochondrial stress is triggered by protein misfolding,it can accelerate abnormal protein aggregation,potentially inducing various diseases.This study developed a cascade-responsive sensor,named AggHX,to monitor the microenvironment of protein aggregation induced by zinc(II)ions and the accompanying mitochondrial dysfunction.The AggHX consists of two key components:(1)A Zn^(2+) þrecognition group for triggering a fluorescent enhance response,and(2)a near-infrared BODIPY scaffold that detects viscosity changes in cell aggregation via HaloTag.This sensor's mechanism of action is elucidated through photochemical and biochemical characterizations.To further investigate the relationship between protein aggregation and mitochondrial homeostasis,we employ fluorescence lifetime imaging microscopy to assess viscosity changes in protein aggregates under intracellular Zn2þstress.This research provides insights into the dynamic behavior and spatial distribution of protein aggregates and mitochondria,contributing to a deeper understanding of their physiological roles in cellular processes and potential implications in disease pathology.
基金supported by the National Key R&D Program of China(2022YFA1207400)the National Natural Science Foundation of China(22274061)+1 种基金the 111 Project(B17019)the Fundamental Research Funds for the Central Universities(CCNU22QN007)。
文摘Changes in cellular viscosity are associated with various physiological processes and pathological conditions.To study these cellular processes and functions,highly sensitive fluorescent probes that detect subtle changes in viscosity are urgently needed but remain lacking.In this study,we present a series of viscosity-responsive near-infrared(NIR)fluorescent probes based on styrene-coated boron dipyrromethene(BODIPY).The probe modified with dimethylaminostyrene and piperazine at the two terminals of the BODIPY scaffold showed extremely high viscosity sensitivity values(x,around 1.54),with excellent performance for detecting viscosity below 20 c P.This outstanding property is attributed to the synergistic effects of multiple rotatable bonds and hydrogen-bond interactions.Additionally,this probe has been successfully deployed to monitor viscosity changes in various cellular compartments(i.e.,cytoplasm)and processes(such as during autophagy).This work provides a rational molecular design strategy to construct fluorescent probes with high viscosity sensitivity for exploring cell functions.
基金Research Center for Industries of the Future(RCIF),Westlake UniversityNational Natural Science Foundation of China„Grant/Award Numbers:22007048,22222410Natural Science Foundation of Jiangsu Basic Research Program„Grant/Award Number:BK20221324。
文摘Molecular rotor-based fluorophores(RBFs)activate fluorescence upon increase of micro-viscosity,thus bearing a broad application promise in many fields.However,it remains a challenge to control how fluorescence of RBFs responds to viscosity changes.Herein,we demonstrate that the formation and regulation of intramolecular hydrogen bonds in the excited state of RBFs could modulate their rotational barrier,leading to a rational control of how their fluorescence can be activated by micro-viscosity.Based on this strategy,a series of RBFs were developed based on 4-hydroxybenzylidene-imidazolinone(HBI)that span a wide range of viscosity sensitivity.Combined with the AggTag method that we previously reported,the varying viscosity sensitivity and emission spectra of these probes enabled a dualcolor imaging strategy that detects both protein oligomers and aggregates during the multistep aggregation process of proteins in live cells.In summary,our work indicates that installing intracellular excited state hydrogen bonds to RBFs allows for a rational control of rotational barrier,thus allow for a fine tune of their viscosity sensitivity.Beyond RBFs,we envision similar strategies can be applied to control the fluorogenic behavior of a large group of fluorophores whose emission is dependent on excited state rotational motion,including aggregation-induced emission fluorophores.
