The roles of 3′-exoribonucleases and the exosome in trypanosome mRNA degradation

• Verfasst von: Fadda, Abeer [VerfasserIn]
• Verfasst von: Färber, Valentin Lutz Fabian [VerfasserIn]
• Verfasst von: Droll, Dorothea [VerfasserIn]
• Verfasst von: Clayton, Christine [VerfasserIn]
• Titel: The roles of 3′-exoribonucleases and the exosome in trypanosome mRNA degradation
• Verf.angabe: Abeer Fadda, Valentin Färber, Dorothea Droll, and Christine Clayton
• E-Jahr: 2013
• Jahr: May 22, 2013
• Umfang: 11 S.
• Fussnoten: Gesehen am 19.02.2021
• Titel Quelle: Enthalten in: RNA
• Ort Quelle: Cold Spring Harbor, NY : Laboratory Press, 1995
• Jahr Quelle: 2013
• Band/Heft Quelle: 19(2013), 7, Seite 937-947
• ISSN Quelle: 1469-9001
• DOI: doi:10.1261/rna.038430.113
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: CAF1
• Sach-SW: deadenylation
• Sach-SW: exosome
• Sach-SW: mRNA decay
• Sach-SW: mRNA degradation
• Sach-SW: PAN2
• Sach-SW: Trypanosoma
• K10plus-PPN: 1748722220

Abstract

The degradation of eukaryotic mRNAs can be initiated by deadenylation, decapping, or endonuclease cleavage. This is followed by 5′-3′ degradation by homologs of Xrn1, and/or 3′-5′ degradation by the exosome. We previously reported that, in African trypanosome Trypanosoma brucei, most mRNAs are deadenylated prior to degradation, and that depletion of the major 5′-3′ exoribonuclease XRNA preferentially stabilizes unstable mRNAs. We now show that depletion of either CAF1 or CNOT10, two components of the principal deadenylation complex, strongly inhibits degradation of most mRNAs. RNAi targeting another deadenylase, PAN2, or RRP45, a core component of the exosome, preferentially stabilized mRNAs with intermediate half-lives. RRP45 depletion resulted in a 5′ bias of mRNA sequences, suggesting action by a distributive 3′-5′ exoribonuclease. Results suggested that the exosome is involved in the processing of trypanosome snoRNAs. There was no correlation between effects on half-lives and on mRNA abundance.