PXD061279

PXD061279 is an original dataset announced via ProteomeXchange.

Title	A molecular switch at the yeast mitoribosomal tunnel exit controls cytochrome b synthesis
Description	Mitochondrial gene expression needs to be balanced with cytosolic translation to produce oxidative phosphorylation complexes. In yeast, translational feedback loops involving lowly expressed proteins called translational activators help to achieve this balance. Synthesis of cytochrome b (Cytb or COB), a core subunit of complex III in the respiratory chain, is controlled by three translational activators and the assembly factor Cbp3-Cbp6. However, the molecular interface between the COB translational feedback loop and complex III assembly is yet unknown. Here, using protein-proximity mapping combined with selective mitoribosome profiling, we reveal the components and dynamics of the molecular switch controlling COB translation. Specifically, we demonstrate that Mrx4, a previously uncharacterized ligand of the mitoribosomal polypeptide tunnel exit, interacts with either the assembly factor Cbp3-Cbp6 or with the translational activator Cbs2. These reciprocal interactions determine whether the translational activator complex with bound COB mRNA can interact with the mRNA channel exit on the small ribosomal subunit for translation initiation. Organization of the feedback loop at the tunnel exit therefore orchestrates mitochondrial translation with respiratory chain biogenesis
HostingRepository	PRIDE
AnnounceDate	2025-07-11
AnnouncementXML	Submission_2025-07-11_06:05:02.126.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Ignasi Forne
SpeciesList	scientific name: Saccharomyces cerevisiae (Baker's yeast); NCBI TaxID: 4932;
ModificationList	No PTMs are included in the dataset
Instrument	Q Exactive HF

Revision	Datetime	Status	ChangeLog Entry
0	2025-02-27 11:48:26	ID requested
⏵ 1	2025-07-11 06:05:02	announced

10.1093/NAR/GKAF634;

submitter keyword: Mitochondria, feedback loop, mitochondrial ribosome, protein biogenesis, translation

Dr Martin Ott
contact affiliation	Department of Biochemistry and Biophysics, Stockholm University and Department of Medical Biochemistry and Cell Biology Institute of Biomedicine University of Gothenburg Medicinaregatan 9A 41390 Göteborg (Sweden)
contact email	martin.ott@gu.se
lab head
Ignasi Forne
contact affiliation	Biomedical Center-LMU
contact email	ignasi.forne@lrz.uni-muenchen.de
dataset submitter

Dataset FTP location NOTE: Most web browsers have now discontinued native support for FTP access within the browser window. But you can usually install another FTP app (we recommend FileZilla) and configure your browser to launch the external application when you click on this FTP link. Or otherwise, launch an app that supports FTP (like FileZilla) and use this address: ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2025/07/PXD061279

PRIDE project URI

• PRIDE
  1. PXD061279
     1. Label: PRIDE project
     2. Name: A molecular switch at the yeast mitoribosomal tunnel exit controls cytochrome b synthesis