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Photoaffinity labeling of transcription factors by DNA-templated crosslinking.

ABSTRACT: Characterization of transcription factor-DNA interaction is of high importance in elucidating the molecular mechanisms of gene transcriptions. DNA-based affinity probes were developed to capture and identify transcription factors by covalent crosslinking; however, the requirement of a crosslinker on the affinity probe remains a disadvantage, as the crosslinker itself often interferes with the protein-DNA interactions. We report a dual-probe method able to capture DNA-binding transcription factors with unmodified protein-binding sites in scenarios where conventional probes have failed. We have also shown the method's converse application in selecting specific transcription factor-binding DNA sequences from a probe library and its extension to studying proteins recognizing epigenetic marks. This study may provide a new tool for exploring DNA-binding proteins in biology.

SUBMITTER: Liu Y

PROVIDER: S-EPMC5494549 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Photoaffinity labeling of transcription factors by DNA-templated crosslinking.

Liu Ying Y Zheng Wenlu W Zhang Wan W Chen Nan N Liu Yang Y Chen Li L Zhou Xiaozhou X Chen Xingshuo X Zheng Haifeng H Li Xiaoyu X

Chemical science 20141001 1

Characterization of transcription factor-DNA interaction is of high importance in elucidating the molecular mechanisms of gene transcriptions. DNA-based affinity probes were developed to capture and identify transcription factors by covalent crosslinking; however, the requirement of a crosslinker on the affinity probe remains a disadvantage, as the crosslinker itself often interferes with the protein-DNA interactions. We report a dual-probe method able to capture DNA-binding transcription factor ...[more]

PMID: 28706637

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