Study marks first time the human Mediator complex has been visualized in 3D for human cells

Image of the human Mediator-bound pre-initiation complex. Credit: Yuan HeImage of the human Mediator-bound pre-initiation complex. Credit: Yuan He

The study, “Structure of the human Mediator-bound transcription pre-initiation complex,” was published March 11 in the journal Science. This marks the first time the human Mediator complex has been visualized in 3D in the human cell.

Professor Yuan He of the Department of Molecular Biosciences is the senior author. The co-first authors of the paper are Ryan Abdella and Anna Talyzina, who are graduate students in the He lab.

  • Mediator is crucial to biology, responsible for activating or suppressing genes
  • Complex previously had only been visualized for yeast, not humans
  • Researchers used cryogenic electron microscopy to image the complex’s 56 subunits, then used computational methods to reconstruct a 3D image
  • Mediator plays an active role in many diseases; understanding its structure could lead to new treatments

“This machine is so basic to every branch of modern molecular biology in the context of gene expression,” said Northwestern’s Yuan He, senior author of the study. “Visualizing the structure in 3D will help us answer basic biological questions, such as how DNA is copied to RNA.”

Professor Yuan He photo

Professor Yuan He

Yuan He discusses this research in the Northwestern Now story: “Researchers reveal 3D structure responsible for gene expression – Study marks first time the structure has been visualized in 3D for human cells”

Related:

Professor Yuan He lab website

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