TRANSCRIPTIONAL REGULATION OF BACILLUS-THURINGIENSIS SUBSP ISRAELENSIS MOSQUITO LARVICIDAL CRYSTAL PROTEIN GENE CRYIVA

The cryIVA gene encodes a component of the delta-endotoxin of Bacillus thuringiensis subsp. israelensis. By S1 nuclease mapping and primer e xtension analysis, we have identified the transcriptional initiation s ite of cryIVA. The transcriptional activity from the promoter was dete cted only for the sporulating cells more than 3 h after onset of the s tationary phase. Upstream from the cryIVA transcriptional initiation s ite was found a nucleotide sequence partially homologous to the promot er consensus sequence for the Esigma(E) holoenzyme of Bacillus subtili s. Thus, it was strongly suggested that the identified cryIVA promoter , like some other crystal protein gene promoters, was under the contro l of sigma35, the B. thuringiensis homolog of sigma(E).