Detailed characterisation of the trypanosome nuclear pore architecture reveals conserved asymmetrical functional hubs that drive mRNA export

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F25%3A10497356" target="_blank" >RIV/00216208:11310/25:10497356 - isvavai.cz</a>

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Mjm5DEX2jb" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Mjm5DEX2jb</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1371/journal.pbio.3003024" target="_blank" >10.1371/journal.pbio.3003024</a>

Result language

angličtina

Original language name

Detailed characterisation of the trypanosome nuclear pore architecture reveals conserved asymmetrical functional hubs that drive mRNA export

Original language description

Nuclear export of mRNAs requires loading the mRNP to the transporter Mex67/Mtr2 in the nucleoplasm, controlled access to the pore by the basket-localised TREX-2 complex and mRNA release at the cytoplasmic site by the DEAD-box RNA helicase Dbp5. Asymmetric localisation of nucleoporins (NUPs) and transport components as well as the ATP dependency of Dbp5 ensure unidirectionality of transport. Trypanosomes possess homologues of the mRNA transporter Mex67/Mtr2, but not of TREX-2 or Dbp5. Instead, nuclear export is likely fuelled by the GTP/GDP gradient created by the Ran GTPase. However, it remains unclear, how directionality is achieved since the current model of the trypanosomatid pore is mostly symmetric. We have revisited the architecture of the trypanosome nuclear pore complex using a novel combination of expansion microscopy, proximity labelling and streptavidin imaging. We could confidently assign the NUP76 complex, a known Mex67 interaction platform, to the cytoplasmic site of the pore and the NUP64/NUP98/NUP75 complex to the nuclear site. Having defined markers for both sites of the pore, we set out to map all 75 trypanosome proteins with known nuclear pore localisation to a subregion of the pore using mass spectrometry data from proximity labelling. This approach defined several further proteins with a specific localisation to the nuclear site of the pore, including proteins with predicted structural homology to TREX-2 components. We mapped the components of the Ran-based mRNA export system to the nuclear site (RanBPL), the cytoplasmic site (RanGAP, RanBP1) or both (Ran, MEX67). Lastly, we demonstrate, by deploying an auxin degron system, that NUP76 holds an essential role in mRNA export consistent with a possible functional orthology to NUP82/88. Altogether, the combination of proximity labelling with expansion microscopy revealed an asymmetric architecture of the trypanosome nuclear pore supporting inherent roles for directed transport. Our approach delivered novel nuclear pore associated components inclusive positional information, which can now be interrogated for functional roles to explore trypanosome-specific adaptions of the nuclear basket, export control, and mRNP remodelling.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10600 - Biological sciences

Project

<a href="/en/project/GC21-19503J" target="_blank" >GC21-19503J: Mapping mRNP-NUP interactions during nuclear export with a unique mRNA-trap</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2025

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

PLoS Biology

ISSN

1544-9173

e-ISSN

1545-7885

Volume of the periodical

23

Issue of the periodical within the volume

2

Country of publishing house

US - UNITED STATES

Number of pages

30

Pages from-to

e3003024

UT code for WoS article

001413584800004

EID of the result in the Scopus database

2-s2.0-85216958200