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Improved Red Fluorescent Redox Indicators for Monitoring Cytosolic and Mitochondrial Thioredoxin Redox Dynamics.

ABSTRACT: Thioredoxin (Trx) is one of the major thiol-dependent antioxidants in living systems. The study of Trx functions in redox biology was impeded by the lack of practical tools to track Trx redox dynamics in live cells. Our previous work developed TrxRFP1, the first genetically encoded fluorescent indicator for Trx redox. In this work, we report an improved fluorescent indicator, TrxRFP2, for tracking the redox of Trx1, which is primarily cytosolic and nuclear. Furthermore, because mitochondria specifically express Trx2, we have created a new genetically encoded fluorescent indicator, MtrxRFP2, for the redox of mitochondrial Trx. We characterized MtrxRFP2 as a purified protein and used subcellularly localized MtrxRFP2 to image mitochondrial redox changes in live cells.

SUBMITTER: Pang Y

PROVIDER: S-EPMC8906223 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Improved Red Fluorescent Redox Indicators for Monitoring Cytosolic and Mitochondrial Thioredoxin Redox Dynamics.

Pang Yu Y Zhang Hao H Ai Hui-Wang HW

Biochemistry 20220208 5

Thioredoxin (Trx) is one of the major thiol-dependent antioxidants in living systems. The study of Trx functions in redox biology was impeded by the lack of practical tools to track Trx redox dynamics in live cells. Our previous work developed TrxRFP1, the first genetically encoded fluorescent indicator for Trx redox. In this work, we report an improved fluorescent indicator, TrxRFP2, for tracking the redox of Trx1, which is primarily cytosolic and nuclear. Furthermore, because mitochondria spec ...[more]

PMID: 35133140

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