Isolation of mutants of Schizosaccharomycespombe unable to synthesize cadystin, small cadmium-binding peptides

Mutoh, Norihiro; Hayashi, Yukimasa

doi:10.1016/0006-291x(88)90555-4

Cited by 127 publications

(74 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3, A and B, and 4, A-C), acid-labile sulfide (Table I), and a peptide SH:Cd molar ratio near 1 and eluted a little later than Cyt C . These features permit designation of this complex as the high-molecular-weight complex found in yeasts and other plants (Murasugi et al, 1983;Jackson et al, 1984;Mutoh and Hayashi, 1988;Reese et al, 1992;Speiser et al, 1992). Nothing in regions I1 and I11 indicated the presence of the less abundant sulfide-free, low-molecular-weight Cd-binding complex (Murasugi et al, 1983;Jackson et al, 1984;Kneer and Zenk, 1992).…”

Section: Sulfide In Cd-binding Complexesmentioning

confidence: 99%

“…The Cd-binding complexes may be low and high molecular weight (Murasugi et al, 1983;Jackson et al, 1984;Kneer and Zenk, 1992). The high-molecular-weight complex is essential for sustained growth in high concentrations of Cd (Mutoh and Hayashi, 1988) and contains acid-labile sulfide (Murasugi et al, 1983;Speiser et al, 1992). Those complexes from the yeasts Schizosaccharomyces pombe and Candida glabrata with S2-:Cd molar ratios exceeding 0.4 had CdS crystallites surrounded by yECG, (yEC),G, and (yEC), (Dameron et al, 1989).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Retention of Cadmium in Roots of Maize Seedlings (Role of Complexation by Phytochelatins and Related Thiol Peptides)

1995

View full text Add to dashboard Cite

show abstract

Section: Sulfide In Cd-binding Complexesmentioning

confidence: 99%

mentioning

confidence: 99%

Retention of Cadmium in Roots of Maize Seedlings (Role of Complexation by Phytochelatins and Related Thiol Peptides)

1995

View full text Add to dashboard Cite

show abstract

“…Phytochelatins (PCs) play an essential role in heavy-metal detoxification in plants and fungi (2,3). PCs chelate heavy metals and then PC-metal complexes are translocated across the tonoplast and sequestered in vacuoles (4,5), thus decreasing the heavy-metal content in the cytosol of yeast and plant cells.…”

mentioning

confidence: 99%

Long-distance root-to-shoot transport of phytochelatins and cadmium in Arabidopsis

Gong

Lee²,

Schroeder³

2003

Proc. Natl. Acad. Sci. U.S.A.

312

234

View full text Add to dashboard Cite

Phytochelatin synthases (PCS) mediate cellular heavy-metal resistance in plants, fungi, and worms. However, phytochelatins (PCs) are generally considered to function as intracellular heavymetal detoxification mechanisms, and whether long-distance transport of PCs occurs during heavy-metal detoxification remains unknown. Here, wheat TaPCS1 cDNA expression was either targeted to Arabidopsis roots with the Arabidopsis alcohol dehydrogenase (Adh) promoter (Adh:: TaPCS1͞cad1 C admium is a widespread nonessential toxic heavy metal, released into the biosphere mostly by modern industry (1). Phytochelatins (PCs) play an essential role in heavy-metal detoxification in plants and fungi (2, 3). PCs chelate heavy metals and then PC-metal complexes are translocated across the tonoplast and sequestered in vacuoles (4, 5), thus decreasing the heavy-metal content in the cytosol of yeast and plant cells. PCs are synthesized from glutathione by the enzyme PC synthase (PCS) (6-9). However, PC research has focused mainly on PC transport into vacuoles (4, 5), and it remains unknown whether long-distance transport of PCs or PCS occurs in plants.Cd 2ϩ is taken up by plants, and plants have been proposed to provide an efficient system for heavy-metal removal from soils (10, 11). Soil composition affects Cd 2ϩ sensitivity. For example, silicon in soil reduces heavy-metal sensitivity (12, 13). Normally, Cd 2ϩ concentrations in roots are at least 10 times greater than those in shoots (14). However, for efficient phytoextraction from soils, heavy metals must be translocated into aerial tissues for later harvest. Translocation of Cd 2ϩ from roots to shoots has been studied in diverse plant species (15-18) and has been proposed to occur via the xylem of Indian mustard in a PCindependent manner (16). The molecular mechanisms for rootto-shoot Cd 2ϩ transport remain largely unknown, and PCs are predicted not to undergo long-distance transport but to enhance vacuolar heavy-metal sequestration in the cells in which they are produced.The cad1-3 mutant is a recessive, loss-of-function mutation in the Arabidopsis AtPCS1 gene (7) (9) by PCR. The TaPCS1 PCR fragment was subcloned into pBluescript II SK(ϩ) vector. A 3ϫ myc tag DNA sequence was constructed by PCR recovery from a plasmid containing c-myc and then subcloned into the pGEM-T Easy vector (Promega). The subcloned myc fragment was recovered with SpeI and SacI enzymes and then fused to the 3Ј end of the TaPCS1 ORF in the pBluescript II SK(ϩ) vector at the SpeI site. All PCR products were confirmed by sequencing (Retrogen, La Jolla, CA). The fusion sequence was then digested with BamHI and SacI and subcloned into the binary expression vector pBI121, either with the cauliflower mosaic virus 35S or the Arabidopsis alcohol dehydrogenase (Adh) promoter (20). Both constructs were transformed into the PC-deficient Arabidopsis mutant cad1-3 by direct Agrobacterium tumefaciens-mediated transformation using the floral dip technique (21). T2 seeds with 3:1 segregation on kanamycin plates were used for hom...

show abstract

“…Additional evidence to suggest that GSH is a precursor of ('yEC)nG includes an observed depletion of GSH and concomitant synthesis of (yEC)nG when plants or cells are exposed to Cd (8,17,23), replacement of the Gly by #-alanine in the (7EC)nG homologues of plants that use the corresponding homologue of GSH (6), the inability of Schizosaccharamyces pombe mutants that lack GSH biosynthetic enzymes to synthesize these peptides (15), and an observed inhibition of(yEC)nG biosynthesis by buthionine sulfoximine (8,20,23,25). Buthionine sulfoximine is a specific inhibitor of -y-glutamylcysteinyl synthetase (EC 6.3,2,21), an enzyme of the GSH biosynthetic pathway (5).…”

mentioning

confidence: 99%

Poly(γ-glutamylcysteinyl)glycine Synthesis in Datura innoxia and Binding with Cadmium

Delhaize¹,

Jackson²,

Lujan³

et al. 1989

Plant Physiol.

115

View full text Add to dashboard Cite

The effects of Cd on poly('y-glutamylcysteinyl)glycine [('yEC),G] biosynthesis and formation of ('yEC),G:Cd complexes were measured in two cell lines of Datura innoxia with differing Cd tolerance. In addition, RNA synthesis, protein synthesis, and GSH concentrations were measured during a 48 hour exposure to Cd. Exposure to 250 micromolar CdCI2 was toxic to the sensitive line, whereas the tolerant line survived and grew in its presence. Cd-sensitive cells synthesized the same amount of (yEC),G as tolerant cells during an initial 24 hour exposure to 250 micromolar CdC12. However, rates of ('yEC),G:Cd complex formation differed between the two cell lines with the sensitive cells forming complexes later than tolerant cells. In addition, the complexes formed by sensitive cells were of lower molecular weight than those of tolerant cells and did not bind all of the cellular Cd.Pulse-labeling of cells with L-[3S]cysteine resulted in equivalent rates of incorporation into the ('yEC)nG of both cell lines during the initial 24 hours after Cd. Rates of protein and RNA synthesis were similar for both cell lines during the initial 8 hours after Cd but thereafter declined rapidly in sensitive cells. This was reflected by a decline in viability of sensitive cells. The GSH content of both cell lines declined rapidly upon exposure to Cd but was higher in sensitive cells throughout the experiment. These results show that the biosynthetic pathway for (-yEC)nG synthesis in sensitive cells is operational and that relative overproduction of (yEC),G is not the mechanism of Cd-tolerance in a Cd-tolerant cell line of D. innoxia. Rapid formation of ('yEC)nG:Cd complexes that bind all of the cellular Cd within 24 hours appears to correlate with tolerance in these cells.Whole plants and plant cells in culture respond to Cd stress by synthesizing (yEC)nG3 (where n = 2 or greater). These compounds are also known by the following names: cadystin, phytochelatin, 'y-glutamyl metal binding peptide, Cd-binding polypeptides, and class III metallothioneins

show abstract

Isolation of mutants of Schizosaccharomycespombe unable to synthesize cadystin, small cadmium-binding peptides

Cited by 127 publications

References 11 publications

Retention of Cadmium in Roots of Maize Seedlings (Role of Complexation by Phytochelatins and Related Thiol Peptides)

Retention of Cadmium in Roots of Maize Seedlings (Role of Complexation by Phytochelatins and Related Thiol Peptides)

Long-distance root-to-shoot transport of phytochelatins and cadmium in Arabidopsis

Poly(γ-glutamylcysteinyl)glycine Synthesis in Datura innoxia and Binding with Cadmium

Contact Info

Product

Resources

About