Difference between revisions of "Part:BBa K1442039"

Revision as of 17:05, 16 October 2014

P2A self-cleaving peptide sequence

The self-cleaving 2A peptide (18-22 amino acids) is a virally derived coding region that has been utilised by viruses to self-cleave during translation and is likely to have arisen to overcome traditional IRES sequences due to its much smaller coding length and allows for a smaller viral genome [1].

Of the available 2A coding regions coding for the peptide from various viruses: foot-and-mouth disease virus, equine rhinitis A, Thosea asigna, porcine teschovirus-1. The porcine teschovirus 2A (P2A) had the highest efficiency of cleavage in three mammalian cell lines tested by Kim et al [1]: human, zebrafish and adult mice.

The P2A peptide can be used in a research context to allow multicistronic expression of genes without traditional methods of: multiple promoters, insertion of a splicing signal, insertion of a proteolytic cleavage site (e.g. TEV) and IRESs. Of note, P2A overcomes the limitations of an IRES: it is much smaller and also improves the translational efficiency of IRES-based genes [1]. The use of P2A is therefore useful to allow coexpression of large proteins in plasmids where the size of the insert is limiting and preserves the authenicity of a expressed protein sequence over traditionally cleaved protein in vitro such as TEV protease sites that leave a scar site.

Sequence and Features