Iron starvation leads to increased expression of Cu/Zn‐superoxide dismutase in <i>Aspergillus</i>
抄録
<jats:p>In a search for iron‐regulated proteins of <jats:italic>Aspergillus nidulans</jats:italic> and <jats:italic>Aspergillus fumigatus</jats:italic> a 16‐kDa protein was identified which is about 5‐fold upregulated during iron starvation in both species and which can be approximately 500‐fold enriched by simple one‐step chromatography on Amberlite XAD‐16 resin. N‐terminal protein sequence analysis and cloning of the respective <jats:italic>A. nidulans</jats:italic> cDNA identified this protein as a Cu/Zn‐superoxide dismutase (SODA). Northern analysis revealed that upregulation of <jats:italic>sodA</jats:italic> expression occurs at the level of transcript accumulation. This seems to be a specific low iron response and not a general starvation answer since <jats:italic>sodA</jats:italic> transcript levels do not respond to carbon or nitrogen starvation. In contrast, copper depletion leads to transcriptional downregulation of <jats:italic>sodA</jats:italic>. Furthermore, <jats:italic>sodA</jats:italic> expression was found still to be subject to iron regulation in an <jats:italic>A. nidulans</jats:italic> mutant lacking SREA, a regulator of iron homeostasis, indicating that sodA expression is regulated by an SREA‐independent mechanism. The data presented suggest that SODA plays a protective role under iron deplete conditions.</jats:p>
収録刊行物
-
- FEBS Letters
-
FEBS Letters 485 (2-3), 113-116, 2000-11-21
Wiley
