Riboswitches are functional RNA elements that regulate gene expression by directly detecting metabolites.Twenty years have passed since it was first discovered,researches on riboswitches are becoming increasingly stan...Riboswitches are functional RNA elements that regulate gene expression by directly detecting metabolites.Twenty years have passed since it was first discovered,researches on riboswitches are becoming increasingly standardized and refined,which could significantly promote people’s cognition of RNA function as well.Here,we focus on some representative orphan riboswitches,enumerate the structural and functional transformation and artificial design of riboswitches including the coupling with ribozymes,hoping to attain a comprehensive understanding of riboswitch research.展开更多
Aptamers are a series of high-affinity and high-specificity oligoneucleotides (single-stranded DNA or RNA) to the target, usually selected by the combinatorial chemistry SELEX technique (systematic evolution of ligand...Aptamers are a series of high-affinity and high-specificity oligoneucleotides (single-stranded DNA or RNA) to the target, usually selected by the combinatorial chemistry SELEX technique (systematic evolution of ligands by exponential enrichment). Aptamers have proved to be one kind of novel functional molecules in life science and chemistry. After being labeled by signaling groups, the aptamer probe can conveniently transfer the characteristics of aptamer-target recognition to a form of high-sensitive signal, and the high-affinity, high-specificity measurements of metal ion, organic molecules, nucleic acid, proteins, or cells become possible. This article summarizes the recent advances of aptamer probes in different sensing fields, with special emphasis on aptamer probes as fluorescent sensors.展开更多
Combining the inhibited aptazyme and molecular beacon （MB）, we developed a versatile sensing strategy for amplified detection of adenosine. In this strategy, the adenosine aptamer links to the 8-17 DNAzyme to form a...Combining the inhibited aptazyme and molecular beacon （MB）, we developed a versatile sensing strategy for amplified detection of adenosine. In this strategy, the adenosine aptamer links to the 8-17 DNAzyme to form an aptazyme. A short sequence, denoted as inhibitor, is designed to form a duplex spanning the aptamer-DNAzyme junction, which blocks the catalytic function of the DNAzyme. Only in the presence of target adenosine, the aptamer binds to adenosine, thus the inhibitor dissociates from the aptamer portion of the aptazyme and can no longer form the stable duplex required to inhibit the catalytic activity of the aptazyme. The released DNAzyme domain will hybridize to the MB and catalyze the cleavage in the presence of Zn2＋, making the fluorophore separate from the quencher and resulting in fluorescence signal. The results showed that the detection method has a dynamic range from 10 nmol/L to 1nmol/L, with a detection limit of 10 nmol/L.展开更多
Exosomes have attracted widespread interest due to their inherent advantages in tumor diagnosis and treatment monitoring.However,it is still a big challenge for highly sensitive and specific detection of exosome in re...Exosomes have attracted widespread interest due to their inherent advantages in tumor diagnosis and treatment monitoring.However,it is still a big challenge for highly sensitive and specific detection of exosome in real complexed samples.Herein,a molecular recognition triggered aptazyme cascade strategy was developed for ultrasensitive detection of cancer exosomes in clinical serum samples.In this design,one target exosome could capture a large quantity of aptazymes for the first-step signal amplification.And then the captured aptazyme was activated and recycled to release the fluorophore-labelled substrate strand for a cascaded signal amplification.Notably,the activation of aptazyme only occurs whenithas bound with target exosome,ensuring a low background.The experimental results show that the limit of detection(LOD)and the limit of quantification(LOQ)are 3.5×10^(3) particles/μL and 1.7×10^(4) particles/μL,respectively,which is comparable to the results of most existed fluorescence-based exosome probes.Moreover,this assay possesses high specificity to distinguish exosomes derived from other cell lines.Furthermore,this fluorescence probe was utilized in cancer patient and healthy serum samples successfully,suggesting its great potential for clinical diagnosis and biological studies.展开更多
基金the National Key Research and Development Program of China(2021YFC2100700)the National Natural Science Foundation of China(Grant NSFC-22278313).
文摘Riboswitches are functional RNA elements that regulate gene expression by directly detecting metabolites.Twenty years have passed since it was first discovered,researches on riboswitches are becoming increasingly standardized and refined,which could significantly promote people’s cognition of RNA function as well.Here,we focus on some representative orphan riboswitches,enumerate the structural and functional transformation and artificial design of riboswitches including the coupling with ribozymes,hoping to attain a comprehensive understanding of riboswitch research.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 20575078 and 20705039)
文摘Aptamers are a series of high-affinity and high-specificity oligoneucleotides (single-stranded DNA or RNA) to the target, usually selected by the combinatorial chemistry SELEX technique (systematic evolution of ligands by exponential enrichment). Aptamers have proved to be one kind of novel functional molecules in life science and chemistry. After being labeled by signaling groups, the aptamer probe can conveniently transfer the characteristics of aptamer-target recognition to a form of high-sensitive signal, and the high-affinity, high-specificity measurements of metal ion, organic molecules, nucleic acid, proteins, or cells become possible. This article summarizes the recent advances of aptamer probes in different sensing fields, with special emphasis on aptamer probes as fluorescent sensors.
基金the financial support of the National Natural Science Foundation of China (Nos.21190044,21205032,and 91027000)National Natural Science Foundation of Postdoctoral Scientists of China (No.2013M531779)+1 种基金Hunan Provincial Natural Science Foundation of China (No.13JJ4032)the Fundamental Research Funds for the Central Universities of China.
文摘Combining the inhibited aptazyme and molecular beacon （MB）, we developed a versatile sensing strategy for amplified detection of adenosine. In this strategy, the adenosine aptamer links to the 8-17 DNAzyme to form an aptazyme. A short sequence, denoted as inhibitor, is designed to form a duplex spanning the aptamer-DNAzyme junction, which blocks the catalytic function of the DNAzyme. Only in the presence of target adenosine, the aptamer binds to adenosine, thus the inhibitor dissociates from the aptamer portion of the aptazyme and can no longer form the stable duplex required to inhibit the catalytic activity of the aptazyme. The released DNAzyme domain will hybridize to the MB and catalyze the cleavage in the presence of Zn2＋, making the fluorophore separate from the quencher and resulting in fluorescence signal. The results showed that the detection method has a dynamic range from 10 nmol/L to 1nmol/L, with a detection limit of 10 nmol/L.
基金This work was supported by National Natural Science Founda-tion of China(Nos.21605038 and 21974125)China Postdoctoral Science Foundation(No.2019T120623).
文摘Exosomes have attracted widespread interest due to their inherent advantages in tumor diagnosis and treatment monitoring.However,it is still a big challenge for highly sensitive and specific detection of exosome in real complexed samples.Herein,a molecular recognition triggered aptazyme cascade strategy was developed for ultrasensitive detection of cancer exosomes in clinical serum samples.In this design,one target exosome could capture a large quantity of aptazymes for the first-step signal amplification.And then the captured aptazyme was activated and recycled to release the fluorophore-labelled substrate strand for a cascaded signal amplification.Notably,the activation of aptazyme only occurs whenithas bound with target exosome,ensuring a low background.The experimental results show that the limit of detection(LOD)and the limit of quantification(LOQ)are 3.5×10^(3) particles/μL and 1.7×10^(4) particles/μL,respectively,which is comparable to the results of most existed fluorescence-based exosome probes.Moreover,this assay possesses high specificity to distinguish exosomes derived from other cell lines.Furthermore,this fluorescence probe was utilized in cancer patient and healthy serum samples successfully,suggesting its great potential for clinical diagnosis and biological studies.
