Poster: Late and Moved Abstracts

Abs # 986: Differential expression of transporter genes implicates zinc accumulation and tolerance in the Zn/Cd hyperaccumulator Arabidopsis halleri

Presenter:	Yeh, Kuo-Chen , kcyeh@gate.sinica.edu.tw
Authors	Chiang, Huai-chih  (A)   Yang, Shu-Yi  (A)   Clemens, Stephan  (B)   Wu, Shu-Hsing  (C)   Yeh, Kuo-Chen  (A)
Affiliations:	(A): Institute of BioAgricultural Sciences, Academia Sinica, Taiwan (B): Leibniz-Institut für Pflanzenbiochemie, Germany (C): Institute of Botany, Academia Sinica, Taiwan

By using Arabidopsis cDNA microarray, we compared the gene expression profile of the collected hyperaccumulators, A. halleri and non-hyperaccumulator, A. thaliana. The comparative analysis revealed that the higher expression of heavy metal transporters including P-type ATPase pumps, ZIP and CDF families, the metal binding protein, metallothionein 2b and genes involved in the Halliwell-Asada pathway in A. halleri than in A. thaliana. From the experiments of yeast complementation, we revealed that MTPa2 were functionally complement to zhf mutant in S. pombe. Surprisingly, the expression of EIN2, a positive regulator in ethylene signaling pathway, was lower in A. halleri than in A. thaliana. The possible reduction of ethylene sensitivity may reflect the tolerance to heavy metal stress in A. halleri. The constitutive expression of these genes involving in metal transport, de-toxification and stress sensitivity dominates to the heavy metal tolerance and hyper-accumulation in A. halleri.