PXD074014

PXD074014 is an original dataset announced via ProteomeXchange.

Title	HR3/RORα-mediated cholesterol sensing regulates TOR signaling
Description	Cells and organisms adjust their growth based on the availability of cholesterol, which is essential for cellular functions. However, the mechanisms by which cells sense cholesterol levels and translate these into growth signals are not fully understood. We report that cholesterol rapidly activates the master growth-regulatory TOR pathway in Drosophila tissues. We identify the nuclear receptor HR3, an ortholog of mammalian RORα, as an essential factor in cholesterol-induced TOR activation. We demonstrate that HR3 binds cholesterol and promotes TOR pathway activation through a non-genomic mechanism acting upstream of the Rag GTPases. Similarly, we find that RORα is necessary for cholesterol-mediated TOR activation in human cells, suggesting that HR3/RORα represents a conserved mechanism for cholesterol sensing that couples cholesterol availability to TOR-pathway activity. These findings advance our understanding of how cholesterol influences cell growth, with implications for cholesterol-related diseases and cancer. Here, we demonstrate that dietary cholesterol intake leads to rapid and dynamic activation of the TOR pathway in tissues of Drosophila. This response is modulated by the Drosophila RORα ortholog, HR3, which – like RORα – binds cholesterol and is activated by this ligand. Although HR3 is known to be transcriptionally upregulated by the ecdysone steroid hormone EcR, our results reveal that HR3 regulates growth through the TOR pathway in response to cholesterol independently of ecdysone-mediated effects. This regulation involves rapid cholesterol-induced TOR activation that in part is independent of the transcriptional functions of HR3, through an isoform of HR3 that lacks a DNA-binding domain (DBD). Reducing HR3 levels in cells mitigate the overactivation of TOR caused by the intralysosomal accumulation of cholesterol resulting from depletion of Npc1a. This indicates that HR3 is necessary for TOR activation by lysosomal cholesterol. Our findings suggest that HR3 activates the TOR pathway upstream of Rag proteins. Furthermore, our findings indicate that RORα is involved in cholesterol-induced TOR activation in human cells, suggesting that a conserved function of HR3/RORα is to couple cholesterol levels to TOR-pathway activation
HostingRepository	PRIDE
AnnounceDate	2026-02-10
AnnouncementXML	Submission_2026-02-10_05:03:57.885.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Ivan Bradić
SpeciesList	scientific name: Drosophila melanogaster (Fruit fly); NCBI TaxID: NEWT:7227; scientific name: Homo sapiens (Human); NCBI TaxID: NEWT:9606;
ModificationList	phosphorylated residue
Instrument	Orbitrap Eclipse; Orbitrap Fusion Lumos

Revision	Datetime	Status	ChangeLog Entry
0	2026-02-03 16:38:04	ID requested
⏵ 1	2026-02-10 05:03:58	announced

Dataset with its publication pending

submitter keyword: None

Kim Rewitz
contact affiliation	Department of Biology University of Copenhagen Denmark
contact email	kim.rewitz@bio.ku.dk
lab head
Ivan Bradić
contact affiliation	University of Southern Denmark
contact email	ibradic95@gmail.com
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/PXD074014

PRIDE project URI

• PRIDE
  1. PXD074014
     1. Label: PRIDE project
     2. Name: HR3/RORα-mediated cholesterol sensing regulates TOR signaling