Roles of the Pumilio domain protein PUF3 in Trypanosoma brucei growth and differentiation

• Verfasst von: Marucha, Kevin [VerfasserIn]
• Verfasst von: Clayton, Christine [VerfasserIn]
• Titel: Roles of the Pumilio domain protein PUF3 in Trypanosoma brucei growth and differentiation
• Verf.angabe: K. Kamanyi Marucha and C. Clayton
• E-Jahr: 2020
• Jahr: 9 June 2020
• Umfang: 13 S.
• Fussnoten: Gesehen am 14.09.2020
• Titel Quelle: Enthalten in: Parasitology
• Ort Quelle: Cambridge [u.a.] : Cambridge Univ. Press, 1908
• Jahr Quelle: 2020
• Band/Heft Quelle: 147(2020), 11, Seite 1171-1183
• ISSN Quelle: 1469-8161
• DOI: doi:10.1017/S003118202000092X
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: mRNA decay
• Sach-SW: Pumilio
• Sach-SW: translation
• Sach-SW: Trypanosoma brucei
• K10plus-PPN: 1731779747

Abstract

Trypanosomes strongly rely on post-transcriptional mechanisms to control gene expression. Several Opisthokont Pumilio domain proteins are known to suppress expression when bound to mRNAs. The Trypanosoma brucei Pumilio domain protein PUF3 is a cytosolic mRNA-binding protein that suppresses expression when tethered to a reporter mRNA. RNA-binding studies showed that PUF3 preferentially binds to mRNAs with a classical Pumilio-domain recognition motif, UGUA[U/C]AUU. RNA-interference-mediated reduction of PUF3 in bloodstream forms caused a minor growth defect, but the transcriptome was not affected. Depletion of PUF3 also slightly delayed differentiation to the procyclic form. However, both PUF3 genes could be deleted in cultured bloodstream- and procyclic-form trypanosomes. Procyclic forms without PUF3 also grew somewhat slower than wild-type, but ectopic expression of C-terminally tagged PUF3 impaired their viability. PUF3 was not required for RBP10-induced differentiation of procyclic forms to bloodstream forms. Mass spectrometry revealed no PUF3 binding partners that might explain its suppressive activity. We conclude that PUF3 may have a role in fine-tuning gene expression. Since PUF3 is conserved in all Kinetoplastids, including those that do not infect vertebrates, we suggest that it might confer advantages within the invertebrate host.