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Direct Single-Molecule Observation of Sequential DNA Bending Transitions by the Sox2 HMG Box.

ABSTRACT: Sox2 is a pioneer transcription factor that initiates cell fate reprogramming through locus-specific differential regulation. Mechanistically, it was assumed that Sox2 achieves its regulatory diversity via heterodimerization with partner transcription factors. Here, utilizing single-molecule fluorescence spectroscopy, we show that Sox2 alone can modulate DNA structural landscape in a dosage-dependent manner. We propose that such stoichiometric tuning of regulatory DNAs is crucial to the diverse biological functions of Sox2, and represents a generic mechanism of conferring functional plasticity and multiplicity to transcription factors.

SUBMITTER: Moosa MM

PROVIDER: S-EPMC6321608 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Direct Single-Molecule Observation of Sequential DNA Bending Transitions by the Sox2 HMG Box.

Moosa Mahdi Muhammad MM Tsoi Phoebe S PS Choi Kyoung-Jae KJ Ferreon Allan Chris M ACM Ferreon Josephine C JC

International journal of molecular sciences 20181204 12

Sox2 is a pioneer transcription factor that initiates cell fate reprogramming through locus-specific differential regulation. Mechanistically, it was assumed that Sox2 achieves its regulatory diversity via heterodimerization with partner transcription factors. Here, utilizing single-molecule fluorescence spectroscopy, we show that Sox2 alone can modulate DNA structural landscape in a dosage-dependent manner. We propose that such stoichiometric tuning of regulatory DNAs is crucial to the diverse ...[more]

PMID: 30518054

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