title: Transcriptome Changes in Hirschfeldia incana in Response to Lead Exposure.
abstract: Hirschfeldia incana, a pseudometallophyte belonging to the Brassicaceae 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 (Arabidopsis thaliana) and a Pb tolerant plant (H. incana) 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 MT2b, 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 H. incana treated with Pb, suggesting that ABA-mediated signaling is a possible mechanism in response to Pb treatment in H. incana. This latest finding is an important research direction for future studies.
authors.affiliation: Institut de Recherche pour le Développement, UMR DIADE, Equipe Rhizogenèse Montpellier, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Auguy
authors.affiliation: Centre National de l'Energie, des Sciences et des Techniques Nucléaires, Laboratoire de Biotechnologie des Plantes, UBRM-DSV Rabat, Morocco.
authors.forename: Mouna
authors.initials: M
authors.lastname: Fahr
authors.affiliation: Institut de Recherche pour le Développement, Laboratoire de Microbiologie et Biologie Moléculaire, Faculté des Sciences, Université Mohammed V-Rabat Rabat, Morocco.
authors.forename: Patricia
authors.initials: P
authors.lastname: Moulin
authors.affiliation: Centre National de l'Energie, des Sciences et des Techniques Nucléaires, Laboratoire de Biotechnologie des Plantes, UBRM-DSV Rabat, Morocco.
authors.forename: Mohamed
authors.initials: M
authors.lastname: El Mzibri
authors.affiliation: Laboratoire de Physiologie et Biotechnologie Végétale, Faculté des Sciences, Université Mohammed V-Rabat Rabat, Morocco.
authors.forename: Abdelaziz
authors.initials: A
authors.lastname: Smouni
authors.affiliation: Laboratoire de Microbiologie et Biologie Moléculaire, Faculté des Sciences, Université Mohammed V-Rabat Rabat, Morocco.
authors.forename: Abdelkarim
authors.initials: A
authors.lastname: Filali-Maltouf
authors.affiliation: Institut de Recherche pour le Développement, UMR IPME, Equipe ABIP Montpellier, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Béna
authors.affiliation: Institut National de la Recherche Agronomique, UMR Biochimie et Physiologie Moléculaire des Plantes Montpellier, France.
authors.forename: Patrick
authors.initials: P
authors.lastname: Doumas
keywords: Arabidopsis thaliana; Brassicaceae; Hirschfeldia incana; functional genomics; lead tolerance; transcriptome