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Structure of Saccharomyces cerevisiae Mediator-RNA polymerase II pre-initiation complex for divergent transcription

ABSTRACT: This study has determined structure of transcription initiation complexes including a DNA-bound activator, RNA polymerase II (Pol II), and Mediator on a divergent promoter GAL80/SUT719 using a combination of cryo-EM and XL-MS analyses. Our cryo-EM single-particle analysis reveals a dimeric form of Med-PIC through the Mediator Tail module induced by the activator protein. Density of the upstream DNA bound to the Gal4-VP16 was identifiable along the Mediator Tail module, while XL-MS localized flexible regions that were not visible by cryo-EM analysis, such as activator-binding domains (ABDs and KIX).

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

SUBMITTER: Hee Jong Kim

LAB HEAD: Kenji Murakami

PROVIDER: PXD036149 | Pride | 2024-05-22

REPOSITORIES: Pride

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Structural basis of a transcription pre-initiation complex on a divergent promoter.

Gorbea Colón Jose J JJ Palao Leon L Chen Shin-Fu SF Kim Hee Jong HJ Snyder Laura L Chang Yi-Wei YW Tsai Kuang-Lei KL Murakami Kenji K

Molecular cell 20230201 4

Most eukaryotic promoter regions are divergently transcribed. As the RNA polymerase II pre-initiation complex (PIC) is intrinsically asymmetric and responsible for transcription in a single direction, it is unknown how divergent transcription arises. Here, the Saccharomyces cerevisiae Mediator complexed with a PIC (Med-PIC) was assembled on a divergent promoter and analyzed by cryoelectron microscopy. The structure reveals two distinct Med-PICs forming a dimer through the Mediator tail module, i ...[more]

PMID: 36731470

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