What are peptide aptamers?
Peptide aptamers are small combinatorial proteins that are selected to bind to specific sites on their target molecules. Peptide aptamers consist of short, 5-20 amino acid residues long sequences, typically embedded as a loop within a stable protein scaffold.
What is SELEX used for?
Systematic Evolution of Ligands by EXponential Enrichment (SELEX) is a common method currently used for isolating high-affinity single-stranded (ss) DNAs or RNAs from a large library with random sequences [1,2,3].
What can aptamers bind to?
proteins
In the simplest view, aptamers can be thought of as nucleic acid analogs to antibodies. They are able to bind specifically to proteins, and, in many cases, that binding leads to a modulation of protein activity.
What is an aptamer and why we use it?
Aptamers are oligonucleotide molecules, selected from large libraries to bind a specific target. Aptamers can be used as an antibody alternative in a variety of therapeutic, diagnostic, and target-binding applications.
What is SELEX process?
Specifically, SELEX process includes (1) the incubation of target molecules with the random sequence pools, (2) and the subsequent separation of unbound oligonucleotides and the elution of bound oligonucleotides, (3) then PCR amplification of bound aptamers.
Who discovered SELEX?
Arnold Oliphant and Kevin Struhl had published a beautiful paper in 1989; they synthesized double-stranded DNA with 25 base pairs of fully random sequence (425 sequences) and selected those sequences that bound to the yeast transcription factor GCN4 (Oliphant and Struhl 1989).
How are DNA aptamers made?
Aptamers are generated via an in vitro process known as the Systematic Evolution of Ligands by EXponential enrichment, also known as SELEX. Tuerk and Gold (1990), aiming to find an RNA aptamer sequence that would bind T4 DNA polymerase, first termed the process.
How are aptamers synthesized?
Ease of synthesis: Aptamers can be synthesized using solid phase oligonucleotide synthesis, whereas antibodies have to be obtained using less efficient biochemical or biological methods. This is particularly important if the synthesis is to be scaled up.