The metal induction of these seven genes (czcJ, mmrQ, copQ, mmmQ, mmtQ, and mmsQ/Q1) follows a varied and overlapping response, with very high induction by some metals and no induction by other metals.
The potential involvement of these TFs was further investigated by the research of cis-acting regulatory elements in promoters of genes presenting high induction by the sucrose-atrazine combination (Group V, Figure 3).
By contrast, others showed a higher induction by the Fg don- strain, such as those encoding PR1 (Bradi1g12360) - and PR10-like (Bradi4g05040) proteins (Additional file 3B).
Higher induction by atrazine treatment was also found for the violaxanthin de-epoxidase precursor (At1g08550) gene, which is involved in the xanthophyll cycle (Table 1).
Based on all the above, the initial selection of transcription factors to be analyzed from our quantitative stem trichome database was limited to TFs of the AP2, WRKY and MYC class that showed a 2-fold or higher induction by JA treatment (2.2-fold was the induction rate of control gene SlMTS1; [ 16], renamed SlTPS5[ 21]; Table 5).
For example, in the MmBMM dataset, we found an NF-κB signature in 659 genes, of which 55 also contained an ISRE element; among the 65 NF-κB targets with highest induction by LPS, 12 genes also had an ISRE element.
In contrast, a gene encoding a NADP-dependent alkenal double bond reductase, an enzymatic activity previously shown to be involved in the detoxification of reactive carbonyls in plants [ 41], exhibited a higher induction by the Fg don- strain (Additional file 3B).
Finally group V (cluster N and P) exhibited high induction of expression by combined sucrose-atrazine treatment, which was not produced by additional effects of sucrose alone and atrazine alone.
TUNEL labelling revealed a high induction of apoptosis by a factor of 17.7.
High induction was shown by four genes for keratin 12 that is commonly located in epithelium being involved in interactions between cells and ECM.
In contrast, activation of p53 by cadmium is accompanied by high induction of MT. Besides protecting cells against cadmium-induced oxidative stress and DNA damage, MT may have an essential role in regulating p53 stabilisation and gene transcription, as well as protecting cells against p53-mediated apoptosis.
