PXD067879-1

PXD067879 is an original dataset announced via ProteomeXchange.

Title	The role of methylation in egress and motility initiation in Toxoplasma gondii
Description	Apicomplexan parasites such as Toxoplasma gondii depend on finely tuned cytoskeletal dynamics to invade and exit host cells. A central structure in this process is the conoid, a dynamic apical microtubule-based scaffold that integrates signalling and structural cues to initiate motility. While the lysine methyltransferase AKMT has been implicated in promoting the apical recruitment of the glideosome-associated connector (GAC), which links F-actin to surface adhesins, the broader methylation logic governing motility onset remains unclear. Here, we describe PCKMT, a second apically localized methyltransferase residing at the preconoidal rings, as essential for motility initiation. PCKMT enables the stable recruitment of the formin FRM1, whose actin-nucleating activity drives conoid extrusion and F-actin engagement with other components of the glideosome. In its absence, FRM1 fails to localise apically, conoid protrusion is impaired, and parasites are unable to glide, invade, or egress—despite normal replication and preserved conoid ultrastructure. In contrast, AKMT remains apically localised in PCKMT-deficient parasites but fails to relocalise upon motility activation—a process shown here to depend on FRM1 and actin dynamics. Although AKMT methylates numerous apical proteins, including cytoskeletal factors, the functional consequences of these modifications remain to be elucidated. Together, our findings define a dual methylation checkpoint at the parasite apex: PCKMT anchors FRM1 to license actin assembly, while AKMT reshapes apical architecture through actin-dependent disengagement and GAC recruitment. This layered regulatory system ensures that motility is initiated only when key components are in place, revealing an unappreciated role for lysine methylation in dynamic cellular remodelling.
HostingRepository	PRIDE
AnnounceDate	2026-08-24
AnnouncementXML	Submission_2026-08-24_02:40:25.112.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Ignasi Forne
SpeciesList	scientific name: Toxoplasma gondii RH; NCBI TaxID: NEWT:383379;
ModificationList	methylated residue; iodoacetamide derivatized residue
Instrument	Orbitrap Exploris 480

Revision	Datetime	Status	ChangeLog Entry
0	2025-08-29 09:36:27	ID requested
⏵ 1	2026-08-24 02:40:25	announced

Dataset with its publication pending

submitter keyword: AKMT,Toxoplasma gondii, motility initiation, apical methylation, PCKMT

Prof. Dr. rer. nat. Markus Meissner
contact affiliation	Department of Experimental Parasitology LMU München Lena-Christ-Str. 48 82152 Planegg-Martinsried Telefon: +49 (0) 89 2180 - 3622 Fax: +49 (0) 89 2180 - 3623 E-Mail: markus.meissner@lmu.de
contact email	Markus.Meissner@lmu.de
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/2026/08/PXD067879

PRIDE project URI

• PRIDE
  1. PXD067879
     1. Label: PRIDE project
     2. Name: The role of methylation in egress and motility initiation in Toxoplasma gondii