Oligonucleotides as drug targets

3 Interference with Nucleic Acid Synthesis and Function 

Oligonucleotides are nucleic acid polymers. Each nucleic acid is assembled from a sugar, a nitrogenous heterocyclic base, and a phosphate. The specific identity of the sugar and base determines the type of nucleic acid, which in turn determines the structure and function of the oligonucleotide. 

DNA contains the full genetic blueprint for an organism. Every enzyme, receptor, and structural protein is encoded by DNA in subsections called genes. Collectively, all the genes of an organism comprise its full genome. For humans, the full genome consists of over 3 billion nucleotide pairs.2 

Additional nucleic acids as their triphosphates may add to the 3 end of the existing oligonucleotide. This entire process is catalyzed and controlled by DNA polymerases, a family of enzymes that can replicate and repair DNA. The synthesis of DNA is always performed in the 5 to 3 direction.2 Furthermore, oligonucleotide strands are written with the letters of the nucleic acid monomers, starting from the 5 end. Oligonucleotide abbreviations should be read with an open mind because the literature contains many slightly different notation styles. 

Because of the importance of DNA and the need to keep it as safe and protected as possible, DNA is found only in the restricted environment of the nucleus. Furthermore, it is wound into a compact form to minimize the possibility of damage. When the genetic information of DNA is needed elsewhere in the cell, DNA is partially unwound and 

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Recognize the structural uniqueness of oligonucleotides as drug targets... 

Klinman DM, Klaschik S, Sato T et al (2009) CpG oligonucleotides as adjuvants for vaccines targeting infectious diseases. Adv Drug Deliv Rev 61(3) 248—255... 

Faria M, Ulrich H, The use of synthetic oligonucleotides as protein inhibitors and anticode drugs in cancer therapy accomplishments and limits, Current Cancer Drug Targets, 2 355-36, 2002. 

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