Cloning and characterization of a root specific high‐affinity sulfate transporter from <i>Arabidopsis thaliana</i>

Vidmar, J. John; Tagmount, Abderrahmane; Cathala, Nicole; Touraine, Bruno; Davidian, Jean-Claude

doi:10.1016/s0014-5793(00)01615-x

Cited by 107 publications

(98 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Kinetic analysis of the sulfate uptake isotherm obtained in a range of low sulfate external concentrations (1-50 mM; Fig. 2), revealed that ZmST1;1 has a high affinity for sulfate, with an apparent K m value (14.6 6 0.4 mM) similar to those of other plant high-affinity sulfate transporters (Smith et al, 1995;Smith et al, 1997;Takahashi et al, 2000;Vidmar et al, 2000;Yoshimoto et al, 2002;Howarth et al, 2003). Taken as a whole, our findings suggest a role of ZmST1;1 in mediating the root highaffinity sulfate uptake from the soil solution.…”

Section: Discussionmentioning

confidence: 73%

Heavy Metal Stress and Sulfate Uptake in Maize Roots

et al. 2006

View full text Add to dashboard Cite

ZmST1;1, a putative high-affinity sulfate transporter gene expressed in maize (Zea mays) roots, was functionally characterized and its expression patterns were analyzed in roots of plants exposed to different heavy metals (Cd, Zn, and Cu) interfering with thiol metabolism. The ZmST1;1 cDNA was expressed in the yeast (Saccharomyces cerevisiae) sulfate transporter mutant CP154-7A. Kinetic analysis of sulfate uptake isotherm, determined on complemented yeast cells, revealed that ZmST1;1 has a high affinity for sulfate (K m value of 14.6 6 0.4 mM). Cd, Zn, and Cu exposure increased both ZmST1;1 expression and root sulfate uptake capacity. The metal-induced sulfate uptakes were accompanied by deep alterations in both thiol metabolism and levels of compounds such as reduced glutathione (GSH), probably involved as signals in sulfate uptake modulation. Cd and Zn exposure strongly increased the level of nonprotein thiols of the roots, indicating the induction of additional sinks for reduced sulfur, but differently affected root GSH contents that decreased or increased following Cd or Zn stress, respectively. Moreover, during Cd stress a clear relation between the ZmST1;1 mRNA abundance increment and the entity of the GSH decrement was impossible to evince. Conversely, Cu stress did not affect nonprotein thiol levels, but resulted in a deep contraction of GSH pools. Our data suggest that during heavy metal stress sulfate uptake by roots may be controlled by both GSH-dependent or -independent signaling pathways. Finally, some evidence suggesting that root sulfate availability in Cd-stressed plants may limit GSH biosynthesis and thus Cd tolerance are discussed.To minimize the detrimental effects of heavy metal accumulation, plants have evolved detoxification mechanisms, mainly based on chelation and subcellular compartmentalization (Clemens, 2001). The efficiency of these processes might result in the natural heavy metals tolerance and their basic understanding might be crucial for improving plant performances in phytoextraction of heavy metals from polluted soils (Salt et al., 1998;Pilon-Smits, 2005).Chelation of heavy metals is a ubiquitous detoxification strategy described in a wide variety of plants (Zenk, 1996;Clemens, 2001). One of the principal classes of heavy metal chelators known in plants is phytochelatins (PCs), a family of Cys-rich peptides with the general structure (g-Glu-Cys) n -Gly (n 5 2-11). PCs are synthesized nontranslationally from reduced glutathione (GSH) in a transpeptidation reaction catalyzed by the enzyme PC synthase (PCS; Rea et al., 2004). Their synthesis is induced within minutes following exposure to different metals or metalloids; among these, Cd is the strongest inducer, whereas other metals such as Cu, Zn, Pb, and Ni are less effective and require higher external levels for induction (Grill et al., 1987;Maitani et al., 1996). Interestingly, some inducers, such as Zn, do not seem to serve as substrates for chelation (Clemens, 2001;Souza and Rauser, 2003).The mechanism of heavy metal detoxif...

show abstract

Section: Discussionmentioning

confidence: 73%

Heavy Metal Stress and Sulfate Uptake in Maize Roots

et al. 2006

View full text Add to dashboard Cite

show abstract

“…Judging from the close sequence similarities with other functional sulfate transporters in plants (Smith et al, 1995(Smith et al, , 1997Takahashi et al, 1997Takahashi et al, , 2000Vidmar et al, 1999Vidmar et al, , 2000Shibagaki et al, 2002;Yoshimoto et al, 2002Yoshimoto et al, , 2003Howarth et al, 2003), it is suggested that SULTR4;1 and SULTR4;2 belong to the proton/ sulfate cotransporter family and may use DpH across the tonoplast as a motive force for the efflux of sulfate. Database searches found several other SULTR4 transporters in various plant species.…”

Section: Discussionmentioning

confidence: 99%

“…HVST1 from barley (Hordeum vulgare) showed similar characteristics (Smith et al, 1997;Vidmar et al, 1999). More recently, Arabidopsis thaliana SULTR1;1 and SULTR1;2 (Takahashi et al, 2000;Vidmar et al, 2000;Shibagaki et al, 2002;Yoshimoto et al, 2002) were established to have functional properties similar to SHST1 and HVST1. Arabidopsis SULTR1;1 and SULTR1;2 were localized in the root hairs, epidermis, and cortex cells, and the respective abundances of mRNAs for these transporters increased upon sulfur starvation.…”

Section: Introductionmentioning

confidence: 99%

Vacuolar Sulfate Transporters Are Essential Determinants Controlling Internal Distribution of Sulfate in Arabidopsis

et al. 2004

View full text Add to dashboard Cite

Uptake of external sulfate from the environment and use of internal vacuolar sulfate pools are two important aspects of the acquisition of sulfur for metabolism. In this study, we demonstrated that the vacuolar SULTR4-type sulfate transporter facilitates the efflux of sulfate from the vacuoles and plays critical roles in optimizing the internal distribution of sulfate in Arabidopsis thaliana. SULTR4;1-green fluorescent protein (GFP) and SULTR4;2-GFP fusion proteins were expressed under the control of their own promoters in transgenic Arabidopsis. The fusion proteins were accumulated specifically in the tonoplast membranes and were localized predominantly in the pericycle and xylem parenchyma cells of roots and hypocotyls. In roots, SULTR4;1 was constantly accumulated regardless of the changes of sulfur conditions, whereas SULTR4;2 became abundant by sulfur limitation. In shoots, both transporters were accumulated by sulfur limitation. Vacuoles isolated from callus of the sultr4;1 sultr4;2 double knockout showed excess accumulation of sulfate, which was substantially decreased by overexpression of SULTR4;1-GFP. In seedlings, the supplied [ 35 S]sulfate was retained in the root tissue of the sultr4;1 sultr4;2 double knockout mutant. Comparison of the double and single knockouts suggested that SULTR4;1 plays a major role and SULTR4;2 has a supplementary function. Overexpression of SULTR4;1-GFP significantly decreased accumulation of [ 35 S]sulfate in the root tissue, complementing the phenotype of the double mutant. These results suggested that SULTR4-type transporters, particularly SULTR4;1, actively mediate the efflux of sulfate from the vacuole lumen into the cytoplasm and influence the capacity for vacuolar storage of sulfate in the root tissue. The efflux function will promote rapid turnover of sulfate from the vacuoles particularly in the vasculature under conditions of lowsulfur supply, which will optimize the symplastic (cytoplasmic) flux of sulfate channeled toward the xylem vessels.

show abstract

“…In Arabidopsis, two high-affinity sulfate transporters, SULTR1;1 and SULTR1;2, facilitate the initial uptake of sulfate into the roots (Takahashi et al 2000;Vidmar et al 2000;Shibagaki et al 2002; Yoshimoto et al 2002). These transporters are expressed in the epidermis and cortex of roots, and their transcripts can accumulate through sulfur depletion to maximize sulfate uptake for efficiently using limited amounts of sulfur in the soil environment (Takahashi et al 2000;Vidmar et al 2000;Shibagaki et al 2002; Yoshimoto et al 2002).…”

Section: ϫmentioning

confidence: 99%

“…Accordingly, excess amounts of selenate and chromate taken up from the environment can affect the cellular function of living organisms and sometimes have lethal effects. Indeed, several mutants lacking sulfate transporter genes have been isolated from yeast and plants by using the toxic effects of selenate and chromate as sulfate analogs (Smith et al 1995a, b;Cherest et al 1997;Shibagaki et al 2002).In Arabidopsis, two high-affinity sulfate transporters, SULTR1;1 and SULTR1;2, facilitate the initial uptake of sulfate into the roots (Takahashi et al 2000;Vidmar et al 2000;Shibagaki et al 2002; Yoshimoto et al 2002). These transporters are expressed in the epidermis and cortex of roots, and their transcripts can accumulate through sulfur depletion to maximize sulfate uptake for efficiently using limited amounts of sulfur in the soil environment (Takahashi et al 2000;Vidmar et al 2000;Shibagaki et al 2002; Yoshimoto et al 2002).…”

mentioning

confidence: 99%

Sulfur-responsive promoter of sulfate transporter gene is potentially useful to detect and quantify selenate and chromate

Maruyama‐Nakashita

Inoue

Saito

et al. 2007

Plant Biotechnology

View full text Add to dashboard Cite

Heavy metals are highly toxic for living organisms when excess amounts exist in the environment (Salt et al. 1998;Kovalchuk et al. 2001). Soils and water contaminated with heavy metals cause major environmental and human health problems. During the last few decades, phytoremediation and plant-based assays for cleanup and monitoring of these contaminated environments have been developed (Salt et al. 1998;Kovalchuk et al. 2001;Krizek et al. 2003;Pilon-Smits 2005). These methods take advantage of the sedentary nature of plants, providing inexpensive and nontechnical means of environmental analysis and restoration (Kovalchuk et al. 2001;Krizek et al. 2003).Among heavy metals, selenium and chromium function as toxic analogs of sulfur, and they exist in nature mainly as selenate (SeO 4 2Ϫ) and chromate (CrO 4 2Ϫ ) anions at ϩ6 oxidation states. Because of their structural similarities to sulfate (SO 4 2Ϫ ), selenate and chromate are readily imported into plant cells through the activities of sulfate transporters. In fact, selenate competitively inhibits the influx of sulfate, and after incorporation into the cells, it is subsequently assimilated into selenocysteine and seleno-methionine by sharing the pathways of sulfur metabolism; ultimately, these seleniumcontaining amino acids are incorporated into proteins (Terry et al. 2000;Ellis and Salt 2003). Chromate also has an inhibitory effect on sulfate uptake, but is mainly reduced to ϩ3 oxidation states, Cr 3ϩ or Cr 2 O 3 , presumably by using reducing cofactors. Accordingly, excess amounts of selenate and chromate taken up from the environment can affect the cellular function of living organisms and sometimes have lethal effects. Indeed, several mutants lacking sulfate transporter genes have been isolated from yeast and plants by using the toxic effects of selenate and chromate as sulfate analogs (Smith et al. 1995a, b;Cherest et al. 1997;Shibagaki et al. 2002).In Arabidopsis, two high-affinity sulfate transporters, SULTR1;1 and SULTR1;2, facilitate the initial uptake of sulfate into the roots (Takahashi et al. 2000;Vidmar et al. 2000;Shibagaki et al. 2002; Yoshimoto et al. 2002). These transporters are expressed in the epidermis and cortex of roots, and their transcripts can accumulate through sulfur depletion to maximize sulfate uptake for efficiently using limited amounts of sulfur in the soil environment (Takahashi et al. 2000;Vidmar et al. 2000;Shibagaki et al. 2002; Yoshimoto et al. 2002). The expression of these SULTRs depends on the promoter activities of their 5Ј-regions controlled by sulfur deficiency (Maruyama-Nakashita et al. 2004a, b, 2005. The presence of a specific sulfur-responsive cis-element in the SULTR1;1 promoter region further elaborates the Abstract Plant-based assays for monitoring contaminated environments provide inexpensive and nontechnical means of environmental analysis. Here we report a model system for monitoring selenium and chromium, which are highly toxic heavy metals for living organisms. The major forms of selenium and chromium ...

show abstract

Cloning and characterization of a root specific high‐affinity sulfate transporter from Arabidopsis thaliana

Cited by 107 publications

References 23 publications

Heavy Metal Stress and Sulfate Uptake in Maize Roots

Heavy Metal Stress and Sulfate Uptake in Maize Roots

Vacuolar Sulfate Transporters Are Essential Determinants Controlling Internal Distribution of Sulfate in Arabidopsis

Sulfur-responsive promoter of sulfate transporter gene is potentially useful to detect and quantify selenate and chromate

Contact Info

Product

Resources

About