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Flavin Binding Allosteric Aptamer with Noncovalent Labeling for miR Sensing.

ABSTRACT: Modular allosteric aptamers with discrete recognition and signaling regions provide a facile method of carrying out label-free detection by forgoing complex target labeling requirements. Herein, we describe the design and function of an aptamer scaffold capable of forming a hairpin loop in the presence of FAD (the signaling trigger). The aptamer includes a recognition region for the microRNA (miR) Let-7i. Upon selective miR hybridization, the aptamer undergoes a conformational shift to release FAD and thus produce a measurable response. As a result, the described method can sensitively and selectively detect miR Let-7i with a wide linear range of 0.1 pM to 1 ?M and a detection limit of 150 fM. Additionally, this strategy was able to selectively discriminate between sequences with 1- and 2-nucleotide (nt) differences.

SUBMITTER: Gee A

PROVIDER: S-EPMC7181961 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Flavin Binding Allosteric Aptamer with Noncovalent Labeling for miR Sensing.

Gee A A Grennell J A JA Sitaula S S Jayawickramarajah J J Ali M F MF

Bioconjugate chemistry 20191009 11

Modular allosteric aptamers with discrete recognition and signaling regions provide a facile method of carrying out label-free detection by forgoing complex target labeling requirements. Herein, we describe the design and function of an aptamer scaffold capable of forming a hairpin loop in the presence of FAD (the signaling trigger). The aptamer includes a recognition region for the microRNA (miR) Let-7i. Upon selective miR hybridization, the aptamer undergoes a conformational shift to release F ...[more]

PMID: 31557001

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