PXD069889

PXD069889 is an original dataset announced via ProteomeXchange.

Title	Functional Characterization of Target of Rapamycin (TOR) Signalling in Physcomitrella
Description	Target of rapamycin (TOR) is a structurally and functionally conserved protein kinase and an important signalling hub in eukaryotes. The moss Physcomitrella (Physcomitrium patens) is a model organism for plant physiology, development, and evolution. However, little is known about TOR signalling in non-vascular plants, including Physcomitrella. Here, we report the effects of inhibiting TOR signalling in Physcomitrella. We identified and characterized Physcomitrella 12-kD FK506-binding protein (FKBP12), which binds TOR in the presence of rapamycin. Whereas the growth of wild-type protonema is unaffected by rapamycin treatment, overexpressing endogenous FKBP12 rendered the plant susceptible to the drug in a dose-dependent manner. Likewise, protonema growth was inhibited when the TOR-specific ATP-competitive inhibitor AZD8055 was present in the culture. We show that rapamycin and AZD8055 have pleiotropic effects, as they delay cell cycle progression and development, induce chlorosis, inhibit photosynthesis, and alter total protein content. Additionally, we identified and characterized PpTOR, PpLST8, and PpRAPTOR, key components of TOR complex 1 (TORC1), whereas RICTOR and mSIN1 of TORC2 are absent from the moss genome. We found that PpLst8 substitutes its homolog in yeast to allow cell growth. Physcomitrella mutants were generated with a conditional downregulation of PpTOR, PpLST8, and PpRAPTOR, respectively. These mutants were impaired in growth. Finally, we show TOR-dependent phosphorylation of a well-known TOR phospho-target, the ribosomal protein RPS6, via LC-MS/MS. Collectively, our results suggest that Physcomitrella growth and development is positively controlled by a conserved TOR kinase. We suggest to further dissect TOR signalling in Physcomitrella in order to elucidate signalling integration via TORC1 in plants.
HostingRepository	PRIDE
AnnounceDate	2026-02-09
AnnouncementXML	Submission_2026-02-08_16:20:33.362.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Sebastian Hoernstein
SpeciesList	scientific name: Physcomitrella patens subsp. patens (Moss); NCBI TaxID: NEWT:3218; scientific name: Physcomitrella; NCBI TaxID: NEWT:3217;
ModificationList	phosphorylated residue
Instrument	Q Exactive HF

Revision	Datetime	Status	ChangeLog Entry
0	2025-10-24 13:59:09	ID requested
⏵ 1	2026-02-08 16:20:34	announced

10.1007/s00299-026-03722-y;

Saliba E, Hoernstein SNW, van Gessel N, Sentimenti A, H, ö, ß KMV, Parsons J, Decker EL, Huesgen PF, Simonsen HT, Reski R, Functional characterisation of Target of Rapamycin (TOR) signalling in Physcomitrella. Plant Cell Rep, 45(2):46(2026) [pubmed]

submitter keyword: Physcomitrella, TOR signalling

Pitter Huesgen
contact affiliation	University of Freiburg Faculty of Biology Biochemistry/Functional Proteomics Schänzlestr. 1 79104 Freiburg Germany
contact email	pitter.huesgen@biologie.uni-freiburg.de
lab head
Sebastian Hoernstein
contact affiliation	Biochemistry and Functional Proteomics University of Freiburg
contact email	sebastian.hoernstein@biologie.uni-freiburg.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/2026/02/PXD069889

PRIDE project URI

• PRIDE
  1. PXD069889
     1. Label: PRIDE project
     2. Name: Functional Characterization of Target of Rapamycin (TOR) Signalling in Physcomitrella