Difference between revisions of "Part:BBa K185047"

Revision as of 03:17, 17 October 2009

RelE toxin

The relE toxin is an RNase that preferentially cleaves mRNAs bound to the ribosome at the second position of stop codons. Stop codons not only signal the end of the protein coding sequence but also serve as the binding site for release factors, which promote release of the nascent polypeptide and facilitate recycling of ribosomes for further rounds of translation. Thus truncated mRNA by cleavage of relE lacks appropriate termination signals, which causes the accumulation of stalled ribosomes and these mRNAs are unable to promote release factor binding, nascent polypeptide release, and ribosome recycling. As a result, expression of the relE gene has been shown to severely inhibit translation and prevent colony formation. RelE display codon-specific cleavage of mRNAs in the ribosomal A site, that is to say, among stop codons UAG is cleaved with fast, UAA intermediate and UGA slow rate(UAG>UAA>UGA).

In our design, we add a his-tag at the end of RelE sequence to detect the expression of relE protein. Then we mutated the stop condon from UGA to UAA to make relE toxin inhibit its own traslation moderately.Most importantly, you can get this part in BBa_K185000 or BBa_K185004

Sequence and Features