What are DNA aptamers?
Aptamers are a special class of nucleic acid molecules that are beginning to be investigated for clinical use. These small RNA/DNA molecules can form secondary and tertiary structures capable of specifically binding proteins or other cellular targets; they are essentially a chemical equivalent of antibodies.
How are aptamers designed?
Two major steps exist in aptamer design selection and optimization. In the first step, several polynucleotides with probable binding affinity toward a target are screened by using the SELEX method and then selected. In the second step, aptamers with detected high affinity are shortened, modified, and stabilized.
How aptamers are developed?
Conceptually, aptamers are developed by an evolutionary process, whereby, as selection progresses, sequences with a certain conformation capable of binding to the target of interest emerge and dominate the pool.
How do riboswitches work?
Riboswitches are structured mRNA elements involved in gene regulation that respond to the intracellular concentration of specific small molecules. Binding of their cognate ligand is thought to elicit a global conformational change of the riboswitch, in addition to modulating the fine structure of the binding site.
Where are aptamers found?
Aptamers (from the Latin aptus – fit, and Greek meros – part) are oligonucleotide or peptide molecules that bind to a specific target molecule. Aptamers are usually created by selecting them from a large random sequence pool, but natural aptamers also exist in riboswitches.
Why use RNA aptamers instead of DNA?
Though DNA aptamers are gaining popularity due to the speed and cost savings of DNA aptamer selection and the inherent stability of DNA vs RNA, specific projects will require the unique functionality of RNA.
How do you select RNA aptamers in SELEX?
For RNA aptamer selection, a double-stranded DNA library is transcribed to create the starting RNA library. For RNA aptamers, reverse transcription must be performed in each round of selection to facilitate PCR of DNA and subsequent transcription for the next round of SELEX (1).
Are aptamers targeted to an RNA hairpin more specific than complementary oligonucleotides?
“Aptamers targeted to an RNA hairpin show improved specificity compared to that of complementary oligonucleotides”. Biochemistry. 45 (39): 12076–82. doi: 10.1021/bi0606344.
What is DNA aptamer drug?
This DNA aptamer drug has shown excellent safety profiles, consistent with the low immunogenicity of aptamers and offers a novel strategy for the treatment of a variety of inflammatory diseases with specific DNA aptamers.