The splicing codes

This suggests immediately that splicing is a codified process because 

The two recognition steps are independent because the first step 

0) Take away all 3-letter groups that end with L and substitute them with a blank 

Take away all groups with 5 letters or fewer that begin with O and end with R or G, and join the rest 

We must add however that there is an important difference between splicing and protein synthesis. Whilst the genetic code is practically universal, in the case of splicing there can be different sets of rules in different organisms and we are therefore in the presence of a plurality of splicing codes. 

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Intron DNA base sequence between exons, the protein-coding parts of a DNA sequence of a gene. Intronic sequences are transcribed into mRNA but they are spliced out of the RNA molecule before translation of RNA into protein (see also exon). 

To make mRNA, the primary transcript must be spliced to bring the protein-coding sequences (exons) together and to remove the intervening sequences (introns). The splice signals consist of a 5 and a 3 set of sequences that are always found at splice junctions. However, this is generally believed to provide too little information to recognize a splice site specifically and correctly. Some sequences in the intron are also important. 

Mutations are either exonic or intronic. Missense, deletion and silent mutations are found in the coding region, with intronic mutations being located close to the splice-donor site of the intron following the alternatively... 

Detection of intron/exon splice sites Introns in eukaryotes cause discontinuation of the reading frame. If the analysis is not focused on a cDNA sequence, these introns must be spliced out and the exons joined to form the sequence that actually codes for the protein. Intron/exon splice sites can be predicted based on their common features. Most introns begin with the nucleotides GT and end with the nucleotides AG. There is a branch sequence near the downstream end of each intron involved in the splicing event. 

Removal of introns Maturation of eukaryotic mRNA usually involves the removal of RNA sequences, which do not code for protein (introns, or intervening sequences) from the primary tran script. The remaining coding sequences, the exons, are spliced together to form the mature mRNA. The molecular machine that accomplishes these tasks is known as the spliceosome. [Note A few eukaryotic primary transcripts contain no introns. Others con tain a few introns, whereas some, such as the primary transcripts for the a-chains of collagen, contain more than fifty intervening sequences that must be removed before mature mRNA is ready for translation.]... 

In a nutshell, RNA transcribes the genetic code of the DNA, and transfers it to the cell s protein factories. This process also requires a shearing and splicing of the RNA molecules, because DNA strands contain regions which are not essential for... 

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