Exons are nucleic acid coding sequences that are present in mRNA. Introns are non-coding sequences present in horn that are removed by RNA splicing prior to translation. Intron sequences change dramatically over time, while exon sequences are highly conserved.
What is Introns?
Introns are the insertion sequences between the two exons found in eukaryotes. They do not directly encode proteins. They are removed before mRNA and protein are synthesized.
Therefore, these introns undergo splicing. Introns contain non-coding regions of nucleotides and are not highly conserved. Removal of introns is necessary to prevent the formation of abnormal proteins.
What is Exons?
Exons are the coding sequences that encode the amino acid sequence of a protein. Exons are present in mature mRNA after post-transcriptional modification. These are highly conserved structures, which means they don’t change much over time.
From the outlined differences, we can conclude that the main difference between exons and introns is their function in the genome.
Difference Between Exons and Introns
|
Introns |
Exons |
| Found in Eukaryotes only | Found in both prokaryotes and eukaryotes |
| Non-coding areas of the DNA | Coding areas of the DNA |
| Introns are the non-coding part of hnRNA, which are removed before translation by RNA splicing to form mRNA | Exons are the nucleotide sequence in mRNA, which codes for proteins |
| The sequence of the introns frequently changes over time. In other words, they are less conserved | Exons are highly conserved |
| DNA bases found in between exons | DNA bases that are translated into proteins |
| Introns are removed in the nucleus before the mRNA moves to the cytoplasm | Mature mRNA contains exons and moves to the cytoplasm from the nucleus |
