Transcripts in the Plasmodium Apicoplast Undergo Cleavage at tRNAs and Editing, and Include Antisense Sequences

Nisbet, R. Ellen R.; Kurniawan, Davy P.; Bowers, Harrison D.; Howe, Christopher J.

Abstract

The apicoplast, an organelle found in Plasmodium and many other parasitic apicomplexan species, is a remnant chloroplast that is no longer able to carry out photosynthesis. Very little is known about primary transcripts and RNA processing in the Plasmodium apicoplast, although processing in chloroplasts of some related organisms (chromerids and dinoflagellate algae) shows a number of unusual features, including RNA editing and the addition of 3' poly(U) tails. Here, we show that many apicoplast transcripts are polycistronic and that there is extensive RNA processing, often involving the excision of tRNA molecules. We have identified major RNA processing sites, and have shown that these are associated with a conserved sequence motif. We provide the first evidence for the presence of RNA editing in the Plasmodium apicoplast, which has evolved independently from editing in dinoflagellates. We also present evidence for long, polycistronic antisense transcripts, and show that in some cases these are processed at the same sites as sense transcripts. Together, this research has significantly enhanced our understanding of the evolution of chloroplast RNA processing in the Apicomplexa and dinoflagellate algae.

• Journal Article Type: Article
• Acceptance Date: Jun 23, 2016
• Online Publication Date: Jun 29, 2016
• Publication Date: 2016-08
• Deposit Date: Jun 15, 2020
• Publicly Available Date: Feb 1, 2021
• Journal: Protist
• Print ISSN: 1434-4610
• Electronic ISSN: 1618-0941
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 167
• Issue: 4
• Pages: 377-388
• DOI: https://doi.org/10.1016/j.protis.2016.06.003
• Public URL: https://nottingham-repository.worktribe.com/output/4654748
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S143446101630030X
• Additional Information: This article is maintained by: Elsevier; Article Title: Transcripts in the Plasmodium Apicoplast Undergo Cleavage at tRNAs and Editing, and Include Antisense Sequences; Journal Title: Protist; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.protis.2016.06.003; Content Type: article; Copyright: © 2016 The Authors. Published by Elsevier GmbH.