AUTHOR=Auguy Florence , Fahr Mouna , Moulin Patricia , El Mzibri Mohamed , Smouni Abdelaziz , Filali-Maltouf Abdelkarim , Béna Gilles , Doumas Patrick 

TITLE=Transcriptome Changes in Hirschfeldia incana in Response to Lead Exposure

JOURNAL=Frontiers in Plant Science

VOLUME=6

YEAR=2016

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2015.01231

DOI=10.3389/fpls.2015.01231

ISSN=1664-462X

ABSTRACT=<p><italic>Hirschfeldia incana</italic>, a pseudometallophyte belonging to the <italic>Brassicaceae</italic> family and widespread in the Mediterranean region, was selected for its ability to grow on soils contaminated by lead (Pb). The global comparison of gene expression using microarrays between a plant susceptible to Pb (<italic>Arabidopsis thaliana</italic>) and a Pb tolerant plant (<italic>H. incana</italic>) enabled the identification of a set of specific genes expressed in response to lead exposure. Three groups of genes were particularly over-represented by the Pb exposure in the biological processes categorized as photosynthesis, cell wall, and metal handling. Each of these gene groups was shown to be directly involved in tolerance or in protection mechanisms to the phytotoxicity associated with Pb. Among these genes, we demonstrated that <italic>MT2b</italic>, a metallothionein gene, was involved in lead accumulation, confirming the important role of metallothioneins in the accumulation and the distribution of Pb in leaves. On the other hand, several genes involved in biosynthesis of ABA were shown to be up-regulated in the roots and shoots of <italic>H. incana</italic> treated with Pb, suggesting that ABA-mediated signaling is a possible mechanism in response to Pb treatment in <italic>H. incana</italic>. This latest finding is an important research direction for future studies.</p>