title: Enhanced resistance of yeast mutants deficient in low-affinity iron and zinc transporters to stannous-induced toxicity.
abstract: Tin or stannous (Sn(2+)) compounds are used as catalysts, stabilizers in plastic industries, wood preservatives, agricultural biocides and nuclear medicine. In order to verify the Sn(2+) up-take and toxicity in yeast cells we utilized a multi-elemental analysis known as particle-induced X-ray emission (PIXE) along with cell survival assays and quantitative real-time PCR. The detection of Sn(2+) by PIXE was possible only in yeast cells in stationary phase of growth (STAT cells) that survive at 25mM Sn(2+) concentration. Yeast cells in exponential phase of growth (LOG cells) tolerate only micro-molar Sn(2+) concentrations that result in intracellular concentration below of the method detection limit. Our PIXE analysis showed that STAT XV185-14c yeast cells demonstrate a significant loss of intracellular elements such as Mg, Zn, S, Fe and an increase in P levels after 1h exposure to SnCl(2). The survival assay showed enhanced tolerance of LOG yeast cells lacking the low-affinity iron and zinc transporters to stannous treatment, suggesting the possible involvement in Sn(2+) uptake. Moreover, our qRT-PCR data showed that Sn(2+) treatment could generate reactive oxygen species as it induces activation of many stress-response genes, including SOD1, YAP1, and APN1.
authors: Laboratório de Genotoxicidade - Instituto Royal - Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
authors: Cassiana M
authors: CM
authors: Viau
authors: Jacqueline M
authors: JM
authors: Cardone
authors: Temenouga N
authors: TN
authors: Guecheva
authors: Maria-Lúcia
authors: ML
authors: Yoneama
authors: Jonny F
authors: JF
authors: Dias
authors: Cristina
authors: C
authors: Pungartnik
authors: Martin
authors: M
authors: Brendel
authors: Jenifer
authors: J
authors: Saffi
authors: João A P
authors: JA
authors: Henriques
mesh_terms: D000222:Adaptation, Physiological; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D004785:Environmental Pollutants / Q000378:metabolism / Q000633:toxicity*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D000072105:Superoxide Dismutase-1; D014001:Tin / Q000378:metabolism / Q000633:toxicity*; D015003:Yeasts / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D004785:Environmental Pollutants; D005656:Fungal Proteins; C017800:zinc-binding protein; D014001:Tin; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1