Exon Junction Complex dependent mRNA localization is linked to centrosome organization during ciliogenesis
Résumé
Exon junction complexes (EJCs) mark untranslated spliced mRNAs and are crucial for the
mRNA lifecycle. An imbalance in EJC dosage alters mouse neural stem cell (mNSC) division
and is linked to human neurodevelopmental disorders. In quiescent mNSC and immortalized
human retinal pigment epithelial (RPE1) cells, centrioles form a basal body for ciliogenesis.
Here, we report that EJCs accumulate at basal bodies of mNSC or RPE1 cells and decline
when these cells differentiate or resume growth. A high-throughput smFISH screen identifies
two transcripts accumulating at centrosomes in quiescent cells, NIN and BICD2. In contrast to
BICD2, the localization of NIN transcripts is EJC-dependent. NIN mRNA encodes a core
component of centrosomes required for microtubule nucleation and anchoring. We find that
EJC down-regulation impairs both pericentriolar material organization and ciliogenesis. An
EJC-dependent mRNA trafficking towards centrosome and basal bodies might contribute to
proper mNSC division and brain development.
Domaines
Sciences du Vivant [q-bio]
Origine : Fichiers produits par l'(les) auteur(s)