The plastid-encoded RNA polymerase of plant chloroplasts

authored by: Frederik M. Ahrens, Paula F.V. do Prado, Hauke S. Hillen, Thomas Pfannschmidt
Abstract: Plant chloroplasts possess a dedicated genome (plastome) and a prokaryotic-type plastid-encoded RNA polymerase (PEP) that mediates its expression. PEP is composed of five bacteria-like core proteins and 16 nucleus-encoded PEP-associated proteins (PAPs). These are essential for PEP-driven transcription and chloroplast biogenesis, but their functions and structural arrangement in the PEP complex remained largely enigmatic. Recently, four independently determined cryogenic-electron microscopy (cryo-EM) structures of purified plant PEP complexes reported features of the prokaryotic core and the arrangement of PAPs around it, identified potential functional domains and cofactors, and described the interactions of PEP with DNA. We explore these data and critically discuss the proposed regulatory impact of PAPs on the transcription process. We further address the evolutionary implications and describe fields for future investigation.
Organisation(s): Institute of Botany
External Organisation(s): University of Göttingen
Max-Planck Institute for Multidisciplinary Sciences
Type: Review article
Journal: Trends in plant science
ISSN: 1360-1385
Publication date: 25.02.2025
Publication status: E-pub ahead of print
Peer reviewed: Yes
ASJC Scopus subject areas: Plant Science
Electronic version(s): https://doi.org/10.1016/j.tplants.2025.01.010 (Access: Open)

BibTeX

@article{e615ca6c1ac54c2786ea2bebab7682e0,
title = "The plastid-encoded RNA polymerase of plant chloroplasts",
abstract = "Plant chloroplasts possess a dedicated genome (plastome) and a prokaryotic-type plastid-encoded RNA polymerase (PEP) that mediates its expression. PEP is composed of five bacteria-like core proteins and 16 nucleus-encoded PEP-associated proteins (PAPs). These are essential for PEP-driven transcription and chloroplast biogenesis, but their functions and structural arrangement in the PEP complex remained largely enigmatic. Recently, four independently determined cryogenic-electron microscopy (cryo-EM) structures of purified plant PEP complexes reported features of the prokaryotic core and the arrangement of PAPs around it, identified potential functional domains and cofactors, and described the interactions of PEP with DNA. We explore these data and critically discuss the proposed regulatory impact of PAPs on the transcription process. We further address the evolutionary implications and describe fields for future investigation.",
keywords = "chloroplast, cryo-EM structures, functional predictions, PEP-associated proteins, RNA polymerase, transcription",
author = "Ahrens, {Frederik M.} and {do Prado}, {Paula F.V.} and Hillen, {Hauke S.} and Thomas Pfannschmidt",
note = "Publisher Copyright: {\textcopyright} 2025 The Author(s)",
year = "2025",
month = feb,
day = "25",
doi = "10.1016/j.tplants.2025.01.010",
language = "English",
journal = "Trends in plant science",
issn = "1360-1385",
publisher = "Elsevier Ltd.",
}