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A reactivity-based probe of the intracellular labile ferrous iron pool.

ABSTRACT: Improved methods for studying intracellular reactive Fe(II) are of significant interest for studies of iron metabolism and disease-relevant changes in iron homeostasis. Here we describe a highly selective reactivity-based probe in which a Fenton-type reaction with intracellular labile Fe(II) leads to unmasking of the aminonucleoside puromycin. Puromycin leaves a permanent and dose-dependent mark on treated cells that can be detected with high sensitivity and precision using a high-content, plate-based immunofluorescence assay. Using this new probe and screening approach, we detected alteration of cellular labile Fe(II) in response extracellular iron conditioning, overexpression of iron storage and/or export proteins, and post-translational regulation of iron export. We also used this new tool to demonstrate that labile Fe(II) pools are larger in cancer cells than in nontumorigenic cells.

SUBMITTER: Spangler B

PROVIDER: S-EPMC4990480 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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A reactivity-based probe of the intracellular labile ferrous iron pool.

Spangler Benjamin B Morgan Charles W CW Fontaine Shaun D SD Vander Wal Mark N MN Chang Christopher J CJ Wells James A JA Renslo Adam R AR

Nature chemical biology 20160704 9

Improved methods for studying intracellular reactive Fe(II) are of significant interest for studies of iron metabolism and disease-relevant changes in iron homeostasis. Here we describe a highly selective reactivity-based probe in which a Fenton-type reaction with intracellular labile Fe(II) leads to unmasking of the aminonucleoside puromycin. Puromycin leaves a permanent and dose-dependent mark on treated cells that can be detected with high sensitivity and precision using a high-content, plate ...[more]

PMID: 27376690

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