PROTEIN SPLICING - THE LENGTHS SOME PROTEINS WILL GO TO

We review the recently discovered phenomenon of protein splicing which is the excision of an internal protein sequence at the protein level rather than at the RNA level. The means by which examples of protein s plicing have been identified are described, and the similarities of th e internally spliced protein products (or inteins) are discussed. Comp arisons are made between inteins and group I RNA introns. We describe the evidence supporting excision of intiens by a post-translational au tocatalytic reaction of a full length polypeptide precursor, rather th an by RNA splicing. An examination is made of some of the proposed mec hanism schemes and the supporting them presented.