Is DNA A Protein? Comparison Of Structure, Composition And Functions

Asides from the full name, deoxyribonucleic acid, what else can you say about DNA? DNA is a biomolecule that is always mentioned in the process of protein synthesis and it is easy to assume that it is probably a protein.

DNA is not a protein or biomolecule you can source from food. It is a nucleic acid that carries genetic information in living organisms. It goes through a series of processes that converts it to protein.

All the proteins that help to repair and build tissues, maintain pH, boost immunity and provide the body with energy come from DNA. In this article, you will learn how DNA is used in the synthesis of protein, where this processes occur in living cells and everything in between.

Is DNA made of protein?

DNA is not made of protein. DNA is a nucleic acid made of nucleotide units. Each nucleotide unit consists of a deoxyribose sugar, a phosphate group and a nitrogenous base (any of adenine, guanine, thymine or cytosine).

Does DNA make proteins?

Each DNA sequence is made up of genes which carry a specific set of instructions that code for the synthesis of protein. DNA contains the information needed for protein synthesis, but cannot directly produce protein.

Gene expression is the term that describes the two-step process DNA goes through to produce protein. It involves two processes: transcription and translation.

Transcription takes place in the nucleus of eukaryotes. In this step, a sequence of DNA serves as the template for producing mRNA.

mRNA moves into the cytoplasm where the ribosomes read the nucleotides in pairs of three and translates them into a chain of amino acids. The ribosomes know how to pair the right set to amino acids to make specific proteins.

What are the differences between DNA and protein?

Structure and composition

DNA consists of nucleotide units. Each nucleotide unit is made up of a deoxyribose sugar, a phosphate group and a nitrogenous base, which can be any of adenine, guanine, thymine or cytosine.

Protein consists of units of amino acids. Each amino acid has an amino group, an carboxylic acid group and a unique side chain attached to a central α-carbon atom.

There are only four bases that form DNA and twenty different amino acids that form proteins. A DNA is a double helix with two opposite but complementary strands. The DNA structure is more definite than that of proteins which vary with the type of protein and its functions.

Location in the body

DNA is present in the nucleus, mitochondria and chloroplast of plant cells. But, DNA is more dense in the nucleus, only small amounts are present in the mitochondria and chloroplast.

On the other hand, proteins are present in every part of the cell. While DNA replication occurs in the nucleus of cells, translation into protein occurs in the cytoplasm.


I will start with a DNA function that shows the relationship between DNA and protein. DNA plays a crucial role in gene expression, as mentioned earlier.

It serves as a template for the formation of a new sequence of RNA (mRNA), which codes for various proteins which carry out various functions.

Another function of DNA is replication. DNA replication aids the equal distribution of DNA across all cells during cell division.

In this process, genetic information moves from cell to another and passes down from one generation to another. DNA replication is important in reproduction, cell maintenance, and growth of tissues.

In addition, DNA is at the core of mutations and recombination of genes. DNA is also used in gene therapy, a method that uses the addition of new genes or the repair/replacement of mutated genes to prevent or treat certain diseases.

Other functions include DNA fingerprinting or profiling as a means for identification and DNA repair pathway that helps to maintain homeostasis in cells.

Moving on to the functions of proteins, you will find that they play more general roles. The functions of proteins cut across cellular activities to overall health and wholeness. Some proteins are transcription factors that bind to DNA sites to regulate cell growth, development and differentiation.

Furthermore, proteins are another source of energy for the body in the absence of carbohydrates and fats. Important functions of proteins also include: promoting the building and repair of tissues, regulating enzyme activity, maintaining pH and fluid balance in cells, and the transport of nutrients between cells.

Fibrous proteins such as keratin, elastin and collagen provide structure, flexibility, and rigidity to the skin, hair, nails, connective tissues, arteries, lungs and uterus.

In addition, many hormones are proteins or its derivatives. These hormones are chemical messengers that support communication between cells, tissues and organs. Among these hormones are insulin, glucagon, anti-diuretic hormone (ADH) and human growth hormone (HGH).

What are the differences between DNA and protein electrophoresis?

Electrophoresis is a process that uses electric current to separate molecules, such as protein, DNA & RNA based on their sizes and electrical charge. The process usually uses matrixes, such as gel and SDS-PAGE.

Protein electrophoresis uses SDS-PAGE which contains a polyacrylamide-based discontinuous gel while DNA electrophoresis uses an agarose gel to separate DNA molecules.

Furthermore, the process of running polyacrylamide-based electrophoresis is more technical than the process for agarose gel. Moreover, polyacrylamide gel is more toxic. It is easier to spot DNA stains on agarose gel and under blue or UV light.

The protein gel electrophoresis process is more time-consuming and requires more advanced equipments and solutions.


Why do different segments of DNA produce different proteins?

Different segments of DNA produce different proteins because each gene codes for a different combination of amino acid.

Also, through an alternate process of RNA splicing that can occur between transcription and protein synthesis, one gene may produce several different proteins through the introns and exons.

Is DNA the same as mRNA?

DNA and mRNA are two different nucleic acids. The former is deoxyribonucleic acid and the latter is a subtype of the ribonucleic acid. mRNA, messenger RNA, is a self replicating molecule produced from the transcription step of gene expression. It determines the amino acid sequence of the resulting proteins.

Is mRNA a protein?

mRNA is not a protein. It is a single stranded RNA used in the synthesis of protein. It is the single stranded RNA that is formed in the first stage (transcription) of converting DNA to protein.


DNA is not a protein, nor the other way around. DNA sequences carry the instructions that code for the synthesis of protein. The different genes in DNA sequences code for different amino acids and are used in the synthesis of different proteins.

Gene expression, the process of transcription and translation, is a very crucial process to the metabolism, growth and development of all living cells. The process begins in the nucleus of the cell and continues in the ribosomes in the cytoplasm.

Want to learn more about DNA? See how DNA is described as a macromolecule.

Thanks for reading.