Gasotransmitter Regulation of Phosphatase Activity in Live Cells Studied by Three‐Channel Imaging Correlation

Abstract

Enzyme activity in live cells is dynamically regulated by small‐molecule transmitters for maintaining normal physiological functions. A few probes have been devised to measure intracellular enzyme activities by fluorescent imaging, but the study of the regulation of enzyme activity via gasotransmitters in situ remains a long‐standing challenge. Herein, we report a three‐channel imaging correlation by a single dual‐reactive fluorescent probe to measure the dependence of phosphatase activity on the H2S level in cells. The two sites of the probe reactive to H2S and phosphatase individually produce blue and green fluorescent responses, respectively, and resonance energy transfer can be triggered by their coexistence. Fluorescent analysis based on the three‐channel imaging correlation shows that cells have an ideal level of H2S to promote phosphatase activity up to its maximum. Significantly, a slight deviation from this H2S level leads to a sharp decrease of phosphatase activity. The discovery further strengthens our understanding of the importance of H2S in cellular signaling and in various human diseases.

Crown daisy leaf waste–derived carbon dots: A simple and green fluorescent probe for copper ion

“…The Stern‐Volmer linear equation was ( F 0 ‐ F ) = 5.308 [Cu 2+ ] − 21.96 with a correlation coefficient R 2 of.997, indicating excellent analytical ability in detecting Cu 2+ with a wider detection range. The LOD was calculated to be 1.0nM (S/N = 3) and was much lower than that of previously reported fluorescence CDs probes from other green natural carbon sources (Table ). The wider detection range and lower LOD fully demonstrated that the present N‐CDs from crown daisy leaves were an ideal fluorescent sensor in the detection of Cu 2+ .…”

“…[Cu 2+ ] − 21.96 with a correlation coefficient R 2 of.997, indicating excellent analytical ability in detecting Cu 2+ with a wider detection range. The LOD was calculated to be 1.0nM (S/N = 3) and was much lower than that of previously reported fluorescence CDs probes from other green natural carbon sources 5,7,9,31,39,[42][43][44][45][46][47][48][49][50][51] (Table 1) experiments of the prepared probe toward Cu 2+ were carried out after the probe was stored at 4°C in a refrigerator for 7 days to study its measurement stability, and the result showed no observable change in fluorescence signals, which proved that the prepared N-CD probe had high measurement stability toward Cu 2+ .…”

“…Many methods for Cu 2+ detection have been widely studied, such as inductively coupled plasma–mass spectrometry (ICP‐MS), atomic absorption spectroscopy, electrochemical voltammeter, and fluorescence methods . In comparison with other detection techniques, fluorescence method has outstanding advantages such as simplicity, low cost, easy operation, and high sensitivity . So far, many kinds of fluorescent probe materials including organic molecule, nanoparticle, and semiconductor nanoparticles have been prepared for Cu 2+ detection; nevertheless, these fluorescent probes have disadvantages of requiring complicated synthetic produce, expensive raw materials, and potential high toxicity, which limited their fluorescence sensing applications.…”

“…[4][5][6] In comparison with other detection techniques, fluorescence method has outstanding advantages such as simplicity, low cost, easy operation, and high sensitivity. [7][8][9] So far, many kinds of fluorescent probe materials including organic molecule, 6 nanoparticle, 10,11 and semiconductor nanoparticles 12,13 have been prepared for Cu 2+ detection; nevertheless, these fluorescent probes have disadvantages of requiring complicated synthetic produce, expensive raw materials, and potential high toxicity, which limited their fluorescence sensing applications. Similar to other nanoparticles or semiconductor quantum dots, 14 fluorescence carbon dots (CDs) have also been widely researched as a high fluorescent probe because of their excellent photostability, low toxicity, and favorable biocompatibility.…”

Recent advances in probe design to detect reactive sulfur species and in the chemical reactions employed for fluorescence switching

“…Ou et al (22) reported a dual-reactive fluorescent probe, N 3 -CR-PO 4 , which can detect phosphatase activity and H 2 S at the same time (Fig. 3B); this is useful because H 2 S is thought to be a regulator of phosphatase activity.…”