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bioRxiv · 10.1101/2024.02.16.580782

Architecture of the spinach plastid-encoded RNA polymerase

Wang, T.·Wang, G.·Fang, Y.·Zhang, Y.·Peng, W.·Zhou, Y.·Zhang, A.·Yu, L.-J.·Lu, C.
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Abstract

The plastid-encoded RNA polymerase (PEP) serves as the principal transcription machinery within chloroplasts and is responsible for transcribing over 80% of primary plastid transcripts. Plant PEP is composed of a prokaryotic-like multisubunit core enzyme known as the PEP core, supplemented by newly evolved PEP-associated proteins (PAPs). In this study, we present the cryo-electron microscopy (cryo-EM) structure of a PEP complex derived from spinach (Spinacia oleracea). Our structural analysis unveils the presence of 14 PAPs closely associated with the PEP core complex consisting of 5 subunits, forming an irregular-shaped supercomplex. We provide a detailed depiction of the PEP core subunits and the 14 PAPs, elucidating their precise spatial arrangement and interactions. This research offers a crucial structural basis for future investigations into the functions and regulatory mechanisms governing plastid transcription.

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Wang, T., Wang, G., Fang, Y., Zhang, Y., Peng, W., Zhou, Y., Zhang, A., Yu, L.-J., Lu, C.. 2024-02-17. Architecture of the spinach plastid-encoded RNA polymerase. https://doi.org/10.1101/2024.02.16.580782

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