Physiology and Molecular Biology of Stress ... - KHAM PHA MOI

Table 2. Genes introduced into plants and the effects of their expression on trace elements tolerance, accumulation or
volatilization. Relative values refer to control plants not expressing the transgene. A, Accumulation in the shoot; GSH,
gluthatione; MT, metallothionein; PC, phytochelatin synthase; T, Tolerance; and V, volatilazation
Gene Product Source Target Effect References
merA Hg(II) reductase Gram-Negative Liriodendron T50 µM HgCl 2
; Rugh et al., 1998.
bacteria tulipifera 500 mg HgCl 2
Kg -1
Nicotiana V Hg-volatilisation rate increased ten-fold Heaton et al., 1998.
tabacum
merA Hg(II) reductase Gram-negative A. thaliana T 10 µM CH 3
HgCl(>40-fold) Bizili et al., 2000.
merB Organomercurial bacteria V Up to 59 pg Hg(0)mg -1 fresh biomass min -1
lyase
merA Hg(II) reductase Gram-negative N. tabacum T 400 µM Phenyl nercuric acetate(PMA) Ruiz et al., 2003.
merB Organomercurial bactereia
lyase
AtPCSI PC A. thaliana A. thaliana T More sensitive to Cd Lee et al., 2003a.
APSI ATP sulfurylase A. thaliana Brassica A Two-fold increase in Se concentrations Pilon-Smits et al.,
juncea T As(III), As(V), Cd, Cu, Hg, Zn 1999.
A Seedlings2.5-fold more As(III), As(V), Hg, Wangeline et al.,
Mo, Pb, V 2004.
Mature plants 2.5-fold more Cd, Cu, Mo, V, W
MT-I M T mouse N. tabacum T 200 µM CdCl 2
(20-fold) Misra and Gedamu
1989; Pan et al.,
1994 a, b.
CUPI MT Saccharomyces B. oleracea T 400 µM CdCl 2
(approx. 16-fold) Hasegawa et al.,
cerevisiae 1997.
Continued...
Heavy Metal Stress
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