Protein splicing
Protein splicing is an intramolecular reaction of certain proteins in which a segment of protein called an intein is cut out of the protein. The resulting N- and C-terminal ends of the protein ( exeins ) are linked so that a continuous peptide chain is created again. The splice point of the starting protein is usually a cysteine or serine ; these amino acids have nucleophilic side chains. All previously known protein splicing processes take place without external energy sources such as ATP.
In contrast to mRNA splicing, protein splicing is one of the post-translational modifications of proteins.
In one
There are four types of inteins: maxi-intein, mini-intein, trans-splicing intein, and alanine -intein . Maxi-inteins are N - and C -terminal splice sites that contain an endonuclease domain. Mini-inteins are also N - and C -terminal splice; however, they do not contain an endonuclease domain. Trans-splicing inteins are inteins divided into N - and C terminus. Alanine inteins have an alanine splice instead of cysteine or serine .
Development of the term splicing
The term splicing has become known in connection with the processing of mRNA. The process of protein splicing was discovered in 1990 by the groups around Anraku and Stevens in Saccharomyces cerevisiae .