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Cryo-EM structure of pioneer factor Cbf1 bound to the nucleosome

ABSTRACT:

SUBMITTER: Priit Eek

PROVIDER: EMPIAR-10875 | biostudies-other |

REPOSITORIES: biostudies-other

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Basic helix-loop-helix pioneer factors interact with the histone octamer to invade nucleosomes and generate nucleosome-depleted regions.

Donovan Benjamin T BT Chen Hengye H Eek Priit P Meng Zhiyuan Z Jipa Caroline C Tan Song S Bai Lu L Poirier Michael G MG

Molecular cell 20230329 8

Nucleosomes drastically limit transcription factor (TF) occupancy, while pioneer transcription factors (PFs) somehow circumvent this nucleosome barrier. In this study, we compare nucleosome binding of two conserved S. cerevisiae basic helix-loop-helix (bHLH) TFs, Cbf1 and Pho4. A cryo-EM structure of Cbf1 in complex with the nucleosome reveals that the Cbf1 HLH region can electrostatically interact with exposed histone residues within a partially unwrapped nucleosome. Single-molecule fluorescenc ...[more]

PMID: 36996811

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