Lariat aptamer: aptamer candidate exclusion by nuclease digestion

摘要

A method for identifying aptamers that bind to target molecules may include contacting an oligonucleotide library with target molecule and digesting unbound oligonucleotides with one or more endonucleases, one or more exonucleases, or one or more endonucleases in combination with one or more exonucleases. The unbound oligonucletides lend themselves to nuclease digestion because their flanking sequences are complementary and form predictable, terminal, secondary structure (a Lariat Aptamer). Bound molecules (aptamers) are protected from nuclease digestion and become enriched. A method for identifying aptamers may further include optionally subjecting selected aptamers to one or more rounds of selection under conditions of increased stringency. A method for identifying aptamers may include yet further amplifying selected aptamers. The described methods may be performed in a screen for identifying aptamers either alone or in combination with other methods typically employed in the art for selecting aptamers (such as, e.g., SELEX). Also contemplated herein are systems and kits for accomplishing the above.