Pubblicazione scientifica

Trypanosomes can initiate nuclear export co-transcriptionally

FILONE TECNOLOGICO	TEMA
trasformazione e commercializzazione

RIASSUNTO

Abstract

The nuclear envelope serves as important messenger RNA (mRNA) surveillance system. In yeast and human, several control systems act in parallel to prevent nuclear export of unprocessed mRNAs. Trypanosomes lack homologues to most of the involved proteins and their nuclear mRNA metabolism is non-conventional exemplified by polycistronic transcription and mRNA processing by trans-splicing. We here visualized nuclear export in trypanosomes by intra- and intermolecular multi-colour single molecule FISH. We found that, in striking contrast to other eukaryotes, the initiation of nuclear export requires neither the completion of transcription nor splicing. Nevertheless, we show that unspliced mRNAs are mostly prevented from reaching the nucleus-distant cytoplasm and instead accumulate at the nuclear periphery in cytoplasmic nuclear periphery granules (NPGs). Further characterization of NPGs by electron microscopy and proteomics revealed that the granules are located at the cytoplasmic site of the nuclear pores and contain most cytoplasmic RNA-binding proteins but none of the major translation initiation factors, consistent with a function in preventing faulty mRNAs from reaching translation. Our data indicate that trypanosomes regulate the completion of nuclear export, rather than the initiation. Nuclear export control remains poorly understood, in any organism, and the described way of control may not be restricted to trypanosomes.

DATA

Data di pubblicazione: 12/11/2018

AUTORI

GOOS CARINA
DEJUNG MARIO
WEHMAN ANN M
M-NATUS ELISABETH
SCHMIDT JOHANNES
SUNTER JACK
ENGSTLER MARKUS
BUTTER FALK
KRAMER SUSANNE

ENTE DI AFFERENZA

DEPT CELL & DEV BIOLOGY BIOCENTER UNIV
INST MOLECULAR BIOLOGY IMB
RUDOLF VIRCHOW CTR UNIV
DEPT BIOLOGICAL & MEDICAL SCIENCES OXFORD BROOKES UNIV OXFORD OX3 0BP UK

RIVISTA

Nucleic Acids Research, 47(1), 266-282

indietro