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bioRxiv · 10.1101/2020.03.01.971028

Structural basis of transcription-translation coupling and collision in bacteria.

Webster, M. W.·Takacs, M.·Zhu, C.·Vidmar, V.·Eduljee, A. D.·Abdelkareem, M.·Weixlbaumer, A.
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Abstract

Prokaryotic messenger RNAs (mRNAs) are translated as they are transcribed. The pioneering ribosome potentially contacts RNA polymerase (RNAP), forming a supramolecular complex known as the expressome. The basis of expressome assembly and its consequences for transcription and translation are poorly understood. Here we present a series of structures representing uncoupled, coupled and collided expressome states determined by electron cryomicroscopy. A bridge between the ribosome and RNAP can be formed by the transcription factor NusG, stabilizing an otherwise variable interaction interface. Shortening of the intervening mRNA causes a substantial rearrangement that aligns the ribosome entrance-channel to the RNAP exit-channel. In this collided complex, NusG-linkage is no longer possible. These structures reveal mechanisms of coordination between transcription and translation and provide a framework for future study. One Sentence SummaryStructures of the molecular assembly executing gene expression shed light on transcription translation coupling.

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Webster, M. W., Takacs, M., Zhu, C., Vidmar, V., Eduljee, A. D., Abdelkareem, M., Weixlbaumer, A.. 2020-03-02. Structural basis of transcription-translation coupling and collision in bacteria.. https://doi.org/10.1101/2020.03.01.971028

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