IscR was also demonstrated to repress hilD and subsequently Spi1 gene expression , consistent with the observation that an IscR mutant is hyper invasive in epithelial cells .
2.4 IscR represses the expression of hilD gene Next , to investigate the regulatory role of IscR on hilD , the expression of the hilD fusion was found to be about 1.5 fold up‐reg-ulated in an iscR muta .
2.4 IscR represses the expression of hilD gene Next , to investigate the regulatory role of IscR on hilD , the expression of the hilD fusion was measured to be about 1.5 fold up‐reg-ulated in an iscR muta .
The iscR mutation led to a 5.5 fold increase in hilD mRNA level compared to the wild‐type strain , confirming that IscR acts as a repressor of hilD .