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Metallo thioneins

Grill, E., Winnacker, E.-L. Zenk, M.H. (1987). Phytochelatins, a class of heavy-metal-binding peptides from plants, are functionally analogous to metallo-thioneins. Proceedings of the National Academy of Sciences, USA, 84, 439-43. [Pg.176]

If animals ingest excessive amounts of Zn(n), Cd (II), Hg(II), or Cu(I) their livers and kidneys accumulate these metals as complexes of proteins called metallo-thioneins/1 e In mammals at least three related genes encode these metal-binding proteins. The best known, metallothionein II, has a highly conserved 61-residue sequence containing 20 cysteine residues and no aromatic residues. [Pg.317]

Resistance Sensitivity to these agents is decreased if cells have elevated glutathione levels or increased DNA repair, or if metallo-thionein (a protein rich in SH groups) is induced. [Pg.406]

Synthesis of Zn-metallo-thionein is stimulated in the liver, which facilitates the retention of zinc by hepatocytes. [Pg.4819]

The mechanism of this eflFect is not known. Hill and Starcher (49) postulated that reduction of copper from its divalent (cupric) state to its monovalent (cuprous) state accounted for the impaired absorption of copper in the presence of ascorbic acid they produced the same effect with another reducing agent, dimercaptopropanol (BAL). This explanation has been accepted by others (56), although the oxidation state of copper for maximum intestinal absorption has not been established. An intramucosal competition of ascorbic acid for sulfhydryl sites on metallo-thioneins was demonstrated (57). If this ligand has any regulatory role in copper uptake, this alternative mechanism of ascorbic acid-copper interaction could explain the mechanism. Experimental confirmation of an ascorbic-acid-induced inhibition of copper absorption in the human intestine has not been presented. [Pg.560]

Nordberg M, Kojima Y (1979) Report from the first international meeting on metallo-thionein and other low molecular mass metal-binding proteins. In Kagi JHR, Nordberg M (eds) Metallothionein, Birkhauser, Basel p 41... [Pg.188]

Leffler P E, Jin T, Nordberg GF. Differential calcium transport disturbances in renal membrane vesicles after cadmlum-metallo-thionein injection in rats. Toxicology 2000 143 227-234. [Pg.527]

These two examples suggest that lifespan is modulated by stress-resistance. Stress-resistance, in turn, is mediated (at least in part) by changes in the levels of stress proteins such as SOD, catalase, metallo-thionein and DNA-repair enzymes. The master-switch role of daf-16 shows that the expression of these genes is coordinated in simple animals. My third example, calorie restriction, suggests that, even in complex animals, the stress response can be coordinated by a relatively simple switch. The profile of the response itself, however, is not always analogous to that in simple organisms. [Pg.259]

UCHIDA Y (1994) Growth inhibitory factor, metallo-thionein-like protein, and neurodegenerative diseases. Biol Signals 3 211-215. [Pg.400]

Humans concluded that there was sufficient evidence for the carcinogenicity of soluble calcium chromate and several relatively insoluble hexavalent chromium compounds in laboratory animals. Tumors were mainly induced at the administration site. In addition, experimental exposure to Be, Cd, Ni, and Sb has caused lung tumors in rats, while various beryllium compounds produced osteosarcomas in rabbits by implantation or injection (Hayes 1997). Rossman et al. (2001) could show a co-carcinogenic action of arsenic with solar UV radiation on mouse skin. Apparently strain as well as species differences of the susceptibility to the action of metals may cause variable outcome of carcinogenicity tests for example, in mice this is caused by higher metallo-thionein levels (Oberdorster et al. 1994, Waalkes and Rehm 1994). [Pg.446]

Mohan P, Failla M, Bremner I, Arthur-Smith A and Kerzner B (1995) Biliary copper excretion in the neonatal rat role of glutathione and metallo-thionein. Hepatology 21 1051-1057. [Pg.749]

Nielson KB, Atkin CL and Winge DR (1985) Distinct metal-binding configurations in metallo-thionein. J Biol Chem 260 5342-5350. [Pg.1082]

Two Cys are found in the N-terminal part of subunit B in the sequence -Cys-Arg-Lys-Ser-Cys- which is similar to -Cys-Lys-Lys-Ser-Cys- found in a ribonucleotide reductase [12] and in several metallo-thioneins [13]. Two more Cys are clustered in the sequence -Cys-Pro-Cys-Arg-Glu- at one third from the N-terminus and the fifth Cys is at two thirds from the N-terminus [14]. Our present results dont allow us to decide which Cys are part of the disulfide bridge and which are linked to the Fe-S cluster [10]. [Pg.2940]

Ozone (1.010.1 ppm) transiently increased IL-6 mRNA showing peak levels at 4 h of ozone exposure in both wild-type and Clara cell secretory protein -/- mice (Mango et al. 1998). Differential metallo-thionein and IL-6 mRNA expression demonstrated increased ozone-induced oxidative stress associated with Clara cell secretory protein deficiency. [Pg.181]

In vivo mercury exposure does induce the synthesis of metallo-thionein in the kidney. The absolute amount of thionein bound mercury, however, usually is small for example, less than 2% of the total renal content at 24 hr after the injection of 0.5 mg Hg2+/kg body weight into the male rat (Webb and Magos, 1976). In contrast, at low-level cadmium exposure, most of the metal accumulated in the kidney is bound to metallothionein. The synthesis of this metalloprotein under these conditions parallels the renal uptake of cadmium until, at least, old age (Cain et al., unpublished). The critical renal concentration at which kidney dysfunction occurs at chronic exposure is high - about 200 yg Cd /g wet weight (Friberg et al., 1974), since only about 20% of this cadmium will be in the toxic non-thionein bound form. [Pg.107]

Simons TJB, Pocock G (1987) Lead enters bovine adrenal medullary cells through calcium channels. J Neurochem 48 383-389 Skroch P, Buchman C, Karin M (1993) Regulation of human and yeast metallo-thionein gene transcription by heavy metal ions. Prog Clin Biol Res 380 113-128... [Pg.75]

Tanaka K, Sueda K, Onosaka S, Okahara K (1975) Fate of Cd-labeled metallo-thionein in rats. Toxicol Appl Pharmacol 33 258-266 Templeton DM, Cherian MG (1983) Cadmium and hypertension. TIPS Rev 4 501-503... [Pg.75]

Mehta, A., Flora, S.J.S., 2001. Possible role of metal redistribution, hepatotoxicity and oxidative stress in chelating agents induced hepatic and renal metallo-thionein in rats. Food Chem. Toxicol. 39, 1029-1038. [Pg.190]


See other pages where Metallo thioneins is mentioned: [Pg.302]    [Pg.334]    [Pg.428]    [Pg.91]    [Pg.511]    [Pg.1070]    [Pg.32]    [Pg.355]    [Pg.358]    [Pg.686]    [Pg.105]    [Pg.121]    [Pg.112]    [Pg.398]    [Pg.670]   
See also in sourсe #XX -- [ Pg.13 , Pg.112 ]




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