TY - JOUR
T1 - Occurrence of Cu-ATPase in Dictyostelium: possible role in resistance to copper
AU - Burlando, B
AU - Evangelisti, V
AU - DONDERO, Francesco
AU - Pons, G
AU - Camakaris, J
AU - VIARENGO, Aldo Giuseppe
N1 - Funding Information:
This work was supported by the Italian National Research Council, Target Project Environmental Biotechnologies, No. 97.01249.PF49.
PY - 2002
Y1 - 2002
N2 - Dictyostelium discoideum amoebae showed an uncommon resistance to Cu2+, as pointed out through cell growth rate (EC50 = 469 ± 30 μM) and the neutral red cytotoxicity assay (EC50 = 334 ± 45 μM). Although no evidence of Cu-inducible metallothionein was found, Cu-dependent ATPase activity was cytochemically detected on pelletted, resin-embedded amoebae. This activity required Cu2+ in the incubation medium, was sensitive to TPEN, vanadate and temperature, and showed dose-dependent increase after exposure of amoebae to 10-500 μM Cu2+ for 7 days. Accordingly, immunofluorescence and Western blotting revealed the occurrence of a Cu-inducible, putative homologue of human Menkes (MNK) Cu-P-type ATPase. To verify if Cu-ATPase is involved in copper resistance, amoebae were exposed to low concentrations of Cu2+ and vanadate followed by the neutral red assay. Exposure to either treatment showed no effect, while a combination caused a dramatic increase of Cu toxicity, possibly depending on Cu-ATPase inhibition.
AB - Dictyostelium discoideum amoebae showed an uncommon resistance to Cu2+, as pointed out through cell growth rate (EC50 = 469 ± 30 μM) and the neutral red cytotoxicity assay (EC50 = 334 ± 45 μM). Although no evidence of Cu-inducible metallothionein was found, Cu-dependent ATPase activity was cytochemically detected on pelletted, resin-embedded amoebae. This activity required Cu2+ in the incubation medium, was sensitive to TPEN, vanadate and temperature, and showed dose-dependent increase after exposure of amoebae to 10-500 μM Cu2+ for 7 days. Accordingly, immunofluorescence and Western blotting revealed the occurrence of a Cu-inducible, putative homologue of human Menkes (MNK) Cu-P-type ATPase. To verify if Cu-ATPase is involved in copper resistance, amoebae were exposed to low concentrations of Cu2+ and vanadate followed by the neutral red assay. Exposure to either treatment showed no effect, while a combination caused a dramatic increase of Cu toxicity, possibly depending on Cu-ATPase inhibition.
UR - https://iris.uniupo.it/handle/11579/31222
U2 - 10.1006/bbrc.2002.6463
DO - 10.1006/bbrc.2002.6463
M3 - Article
SN - 0006-291X
VL - 291
SP - 476
EP - 483
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 3
ER -