Seminar Prof Ian Small

RNA editing in plant organelles comprises abundant pyrimidine transitions, either C-to-U (in almost all land plants) or U-to-C (only in some hornworts, lycophytes and ferns). Both types of RNA editing events are catalysed by RNA-binding pentatricopeptide repeat (PPR) proteins with a C-terminal cytidine deaminase or uridine aminase domain. In hornworts, lycophytes and ferns, C-to-U and U-to-C editing are frequently used to control mRNA translation (via start codon creation or stop codon removal, respectively) in mitochondria and chloroplasts. We would like to copy this novel control mechanism for biotechnological applications in plant organelles. To do this, we are developing synthetic RNA editing enzymes based on the natural proteins that can be designed in principle to recognise any target RNA. Our favoured design comprises S-type PPR motifs based on lycophyte sequences to avoid the reliance on other cofactors shown by angiosperm editing factors. We have developed GRASP (Golden Gate Repeat Assembly for Synthetic PPRs), a high-throughput plate-based kit for efficient assembly of editing enzymes and similarly high-throughput cell-free protein expression assays to test them. Synthetic PPR editing enzymes show promise as broadly applicable molecular tools for editing target mRNAs.

Ian Small, ARC Centre of Excellence in Plants for Space, School of Molecular Sciences, The University of Western Australia, Perth, Australia

Invitation: Hakim Mireau, "Organelles and Reproduction" OrgaRepro team

In connection with the research developed at the Institute Jean-Pierre Bourgin for Plant Sciences.