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Cell-Compatible Nanoprobes for Imaging Intracellular Phosphatase Activities.

ABSTRACT: Phosphatases play an important role in cell biology, but only a few probes are suitable for selectively imaging phosphatase activity in live cells, because the current probes require cell fixation or exhibit considerable cytotoxicity. Herein, we show that conjugating a d-peptide to a quinazolinone derivative generates cell-compatible, biostable probes for imaging the phosphatase activity inside live cells. Moreover, our results show that inhibiting ectophosphatases is a critical factor for imaging intracellular phosphatases. As the first example of using selective inhibitors to ensure intracellular function of molecular probes, this work illustrates a facile approach to design molecular probes for profiling the activities of enzymes in a spatial, selective manner in a complicated environment.

SUBMITTER: Wang J

PROVIDER: S-EPMC6377289 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Cell-Compatible Nanoprobes for Imaging Intracellular Phosphatase Activities.

Wang Jiaqing J Zhou Jie J He Hongjian H Wu Difei D Du Xuewen X Xu Bing B

Chembiochem : a European journal of chemical biology 20181210 4

Phosphatases play an important role in cell biology, but only a few probes are suitable for selectively imaging phosphatase activity in live cells, because the current probes require cell fixation or exhibit considerable cytotoxicity. Herein, we show that conjugating a d-peptide to a quinazolinone derivative generates cell-compatible, biostable probes for imaging the phosphatase activity inside live cells. Moreover, our results show that inhibiting ectophosphatases is a critical factor for imagi ...[more]

PMID: 30388302

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