RNA Splicing | group 1 introns | group 2 introns | self splicing | spliceosome |

The transcription of eukaryotic gene results in formation of premRNA. The pre mRNA have coding sequences and non coding sequences. The coding sequences are known as the exons, while the non coding sequence are known as the introns. splicing is a phenomonon in which the introns are removed and the exons are joined togeather to form mature mRNA. the basic mechanism of splicing is simple. the phosphodiester bond between exon and intron at 5' splice site is first broken, then the 3' hydroxyl group of the 5' exon, reacts with the 3' splice site to complete the reaction.