do Prado, P.F.V.; Ahrens, F.M.; Liebers, M.; Ditz, N.; Braun, H.-P. et al.: Structure of the multi-subunit chloroplast RNA polymerase. In: Molecular Cell 84 (2024), Nr. 5, S. 910-925.e5. DOI:
https://doi.org/10.1016/j.molcel.2024.02.003
Zusammenfassung: |
Chloroplasts contain a dedicated genome that encodes subunits of the photosynthesis machinery. Transcription of photosynthesis genes is predominantly carried out by a plastid-encoded RNA polymerase (PEP), a nearly 1 MDa complex composed of core subunits with homology to eubacterial RNA polymerases (RNAPs) and at least 12 additional chloroplast-specific PEP-associated proteins (PAPs). However, the architecture of this complex and the functions of the PAPs remain unknown. Here, we report the cryo-EM structure of a 19-subunit PEP complex from Sinapis alba (white mustard). The structure reveals that the PEP core resembles prokaryotic and nuclear RNAPs but contains chloroplast-specific features that mediate interactions with the PAPs. The PAPs are unrelated to known transcription factors and arrange around the core in a unique fashion. Their structures suggest potential functions during transcription in the chemical environment of chloroplasts. These results reveal structural insights into chloroplast transcription and provide a framework for understanding photosynthesis gene expression.
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Lizenzbestimmungen: |
CC BY-NC-ND 4.0 Unported - https://creativecommons.org/licenses/by-nc-nd/4.0/
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Publikationstyp: |
Article |
Publikationsstatus: |
publishedVersion |
Erstveröffentlichung: |
2024 |
Schlagwörter (englisch): |
chloroplast, cryo-EM, gene expression, organelle, photosynthesis, plastid, RNA, RNA polymerase, structural biology, transcription
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Fachliche Zuordnung (DDC): |
570 | Biowissenschaften, Biologie
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