Repository landing page
Visualization of Peroxynitrite-Induced Changes of Labile Zn<sup>2+</sup> in the Endoplasmic Reticulum with Benzoresorufin-Based Fluorescent Probes
Abstract
Zn<sup>2+</sup> plays essential roles in biology, and the homeostasis of Zn<sup>2+</sup> is tightly regulated in all cells. Subcellular distribution and trafficking of labile Zn<sup>2+</sup>, and its inter-relation with reactive nitrogen species, are poorly understood due to the scarcity of appropriate imaging tools. We report a new family of red-emitting fluorescent sensors for labile Zn<sup>2+</sup>, ZBR1–3, based on a benzoresorufin platform functionalized with dipicolylamine or picolylamine-derived metal binding groups. In combination, the pendant amines and fluorophore afford an [N<sub>3</sub>O] binding motif that resembles that of previously reported fluorescein-based sensors of the Zinpyr family, reproducing well their binding capabilities and yielding comparable <i>K</i><sub>d</sub> values in the sub-nanomolar and picomolar ranges. The ZBR sensors display up to 8.4-fold emission fluorescence enhancement upon Zn<sup>2+</sup> binding in the cuvette, with similar responses obtained in live cells using standard wide-field fluorescence microscopy imaging. The new sensors localize spontaneously in the endoplasmic reticulum (ER) of various tested cell lines, allowing for organelle-specific monitoring of zinc levels in live cells. Study of ER zinc levels in neural stem cells treated with a peroxynitrite generator, Sin-1, revealed an immediate decrease in labile Zn<sup>2+</sup> thus providing evidence for a direct connection between ER stress and ER Zn<sup>2+</sup> homeostasis- Text
- Journal contribution
- Biophysics
- Biochemistry
- Cell Biology
- Neuroscience
- Biotechnology
- Space Science
- Chemical Sciences not elsewhere classified
- Subcellular distribution
- pendant amines
- cell lines
- imaging tools
- ER stress
- zinc levels
- N 3O binding motif
- Zn
- Kd values
- ZBR sensors display
- ER zinc levels
- endoplasmic reticulum
- reactive nitrogen species
- binding capabilities
- Endoplasmic Reticulum
- Zinpyr family
- picomolar ranges
- emission fluorescence enhancement