What are Nucleic Acids?
Nucleic acids are a group of biomolecules present only in the cell’s nucleus. These nucleic acids are long polymers made of monomeric units called nucleotides: C (cytosine), A (adenine), G (guanine), T (thymine), and U (uracil). There are two types of nucleic acids within the cells: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Both of them have vital functions within the cells.
The DNA molecule is made of two strands of nucleotides (C, A, G, T) polymer chains coiled together into a double-helix pattern. The double helix is stabilized by the hydrogen bonds that forms between the nucleotides bases, as determined by their chemical affinity: adenine with thymine and cytosine with guanine.
The RNA molecule is a single strand polymer composed of the nucleotides C, A, G, and U. However, the RNA molecule can fold itself and acquire secondary structures that are very important to carry out its functions
Importance of Nucleic Acids
The DNA is the biological molecule that stores all the genetic information of the cell (in some viruses RNA may function as the molecule that stores the genetic information). Everything that the cells has to do, at what time in its life cycle, and how it has to do it is determined by the information contained in the DNA molecule. In addition, DNA functions as the molecule that carries on the genetic information from parent to offspring.
RNA is made when the complex biochemical decodification machinery of the cell acts on the DNA to extract the information needed for a particular function. RNA is a key factor for protein synthesis. RNA is responsible for transferring the information contained in the DNA to make a particular protein needed in a specific process for a specific function. Messenger RNA (mRNA) is the nucleic acid that brings information (from the nucleus to the cytoplasm) about which protein to make, and transfer RNA (tRNA) is responsible for transporting aminoacids to the ribosomes to make the required proteins. There is also regulatory RNA, that is RNA molecules capable of regulating gene expression by different mechanisms such as interference or blocking.
Role of Nucleic Acids in Diseases
When an error occurs in any of the steps involved in expressing the genetic information contained in DNA a genetic disease may occur. Understanding how nucleic acids store and deliver genetic information within the cells is necessary to understand diseases and to devise strategies for disease treatment. Many genetic diseases cannot be cured at the moment, but recognizing the importance of nucleic acids in these diseases may be the key that eventually unlocks a cure.
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Bloomfield, V.A., Crothers, D.M., Tinoco, I. (2000). Nucleic acids: structures, properties, and functions. University Science Books. ISBN 0935702490.