Difference Between mRNA And tRNA


RNA also called RiboNucleic Acid, is a single-stranded polymer consisting of nucleotides that are made up of ribose sugar, phosphate, and bases. The bases include adenine, guanine, cytosine, and uracil. It plays a crucial role in gene expression, as it acts as the intermediary between the genetic information that is encoded by DNA and proteins.

R.W. Holley described the structure of RNA in the year 1965. The structure of RNA is similar to that of DNA but the key difference is the ribose sugar in the RNA consists of a hydroxyl group which is absent in the DNA. Here we will discuss the difference between mRNA and tRNA.


There are three main types of RNA in both prokaryotic and eukaryotic cells. They are:

1.mRNA: mRNA is also called messenger RNA. mRNA is 5% of the total RNA present in the cell. Among all the types of RNA, mRNA is the most heterogeneous one in both the base sequence and size. During transcription, mRNA copies the complementary genetic information from DNA in the form of triplet codons of nucleotides.

  • Even though there are 64 codons or triplet bases in the genetic code, only 20 codons represent the amino acids. These codons include 3 stop codons which stop the protein synthesis in the translation process. 

  • During the post transcription process in eukaryotes, the 5’ end of mRNA is capped with guanosine triphosphate nucleotide which helps in the recognition of mRNA during translation or protein synthesis. 

  • In the 3’ end of mRNA, multiple adenylate residues or poly-A tails have been added that help to prevent enzymatic degradation. Hence we can tell that both ends provide stability to the mRNA.

2.tRNA: tRNA also called transfer RNA. tRNA is the smallest RNA among all three types. It has around 75-95 nucleotides. It is the most essential component of translation which helps to transfer the amino acids during protein synthesis. 

  • There is a presence of specific tRNA for each of the 20 amino acids that bind to tRNA and transfer it to the polypeptide chain. During the process of translation of a genetic sequence of mRNA into proteins, tRNA acts as adapters. Hence they are called adapter molecules.

  • The structure of tRNA resembles a cloverleaf that can be stabilized by strong hydrogen bonds in between the nucleotides. 

3.rRNA: rRNA is also called Ribosomal RNA. rRNA is 80% of the total RNA in the cell. Ribosomes are made up of two subunits, they are larger subunits which are called the 50s, and smaller subunits called 30s. 

  • Each of these is made up of its own specific rRNA molecules. The molecules of rRNA are synthesized in the organelle called the nucleolus. 

  • rRNAs combine with enzymes and proteins to form ribosomes in the cytoplasm. These structures are travelled along the mRNA during the process of translation to facilitate the assembly of amino acids to form a polypeptide chain.

mRNA tRNA rRNA Functions

The functions of mRNA tRNA rRNA are as follows:

  • mRNA is produced during the process of transcription which carries the genetic information that is present in the gene from the nucleus to the ribosome in the cytoplasm.

  • rRNA along with the proteins composes the ribosomes, these are the organelles responsible for the protein synthesis.

  • tRNA helps to get the amino acids to the ribosome during the process of translation.

mRNA and tRNA Difference

The difference between mRNA and tRNA are as follow:



It is the connection between genes and protein.

It provides correct amino acids to the ribosomes.

It carries the genetic information from the nucleus to the ribosome. 

It carries amino acids to ribosomes to assist the biosynthesis of protein.

It has a linear structure.

It has a cloverleaf structure.

They are synthesized in the nucleus.

They are synthesized in the cytoplasm.

The size is around 400 to 12,000 nucleotides.

The size is around 75 to 90 nucleotides.

It consists of codons.

It consists of anticodons.

The major types of RNA, mRNA tRNA rRNA plays a significant role in the synthesis of proteins. mRNA is the one that initiates the protein synthesis and it is followed by tRNA and rRNA where the tRNA helps to bring the specific amino acid and the rRNA plays an important role in the formation of ribosomes. And this whole process takes place from the nucleus to the ribosome. 

FAQs (Frequently Asked Questions)

1. What is tRNA?

Ans: tRNA is a small RNA molecule that helps in the synthesis of proteins. Each of the tRNA molecules has two sites: an anticodon region and a region for attachment of amino acids. During the process of translation, a tRNA molecule forms base pairs with the complementary sequence on the mRNA whenever an amino acid is added to the chain to ensure that the appropriate amino acid is added to the protein.

2. What is rRNA?

Ans: rRNA helps in the synthesis of proteins in an organelle called the ribosome. This is further exported to the cytoplasm to translate the genetic information in the mRNA to the protein.

3. What is mRNA? What is the Function of mRNA?

Ans: mRNA is a single-stranded RNA molecule that is complementary to either one of the DNA strands of a gene. It is moved from the cell nucleus to the cytoplasm for the synthesis of proteins. 

Function: During the process of synthesis of proteins an organelle called ribosome is also moved with mRNA which reads the base sequence and uses the genetic information to translate the triplets into respective amino acids.