Copper alone, but not oxidative stress, induces copper-metallothionein gene in Neurospora crassa.
Two metal response elements, flanking an antioxidant response element, were identified in regions upstream (-3730 bp) to copper metallothionein (CuMT) gene of Neurospora crassa. Presence of copper in culture media, but not of pro-oxidants like H2O2 or menadione, induced CuMT gene expression that could not be completely abolished by antioxidants such as N-acetyl cysteine and ascorbic acid. Gel shift assays revealed the ability of nuclear extracts from copper induced cultures to bind PCR-amplified metal response or antioxidant response elements. Similar observations could not be made with cultures exposed either to pro-oxidants or antioxidants. These results differentiate between CuMT gene induction by copper from antioxidant functions associated with the identified upstream elements.
Kumar
K Satish
KS
Department of Biochemistry, University College Science, Osmania University, Hyderabad 500 007, India.
Dayananda
S
S
Subramanyam
C
C
D001205:Ascorbic Acid / Q000378:metabolism; D003300:Copper / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D024202:Electrophoretic Mobility Shift Assay; D015966:Gene Expression Regulation, Fungal; D006861:Hydrogen Peroxide / Q000378:metabolism; D008668:Metallothionein / Q000235:genetics*; D009492:Neurospora crassa / Q000235:genetics* / Q000378:metabolism; D018384:Oxidative Stress; D015533:Transcriptional Activation; D024483:Vitamin K 3 / Q000378:metabolism
D003470:Culture Media; C007121:copper thionein; D024483:Vitamin K 3; D003300:Copper; D008668:Metallothionein; D006861:Hydrogen Peroxide; D001205:Ascorbic Acid