cry1Aa lacks stability elements at its 5'-UTR but integrity of its transcription terminator is critical to prevent decay of its transcript.

We analyzed the influence of the 5' and 3' untranslated regions of the Bacillus thuringiensis cry1Aa on its mRNA stability. Although the cry1Aa gene has a stable transcript (8 min), its 5' UTR did not provide stability to the reporter gene uidA. Stability of cry1Aa could be increased to 40 min by addition of an SP82 stability element at the 5' UTR, suggesting that once the 5' and 3' ends were protected initiation of decay could be effectively blocked.