OpenPlant Co-director Prof Jim Haselhoff (University of Cambridge) recently published his lab’s work on novel DNA tools for protein hyper-expression in Marchantia chloroplasts in BioRxiv.

Comparative analysis of early divergent land plants and construction of DNA tools for hyper-expression in Marchantia chloroplasts.

Eftychios Frangedakis, Fernando Guzman-Chavez, Marius Rebmann, Kasey Markel, Ying Yu, Artemis Perraki, Sze Wai Tse, Yang Liu, Jenna Rever, Susanna Sauret-Gueto, Bernard Goffinet, Harald Schneider and Jim Haseloff.

BioRxiv (2020) 2020.11.27.401802

https://doi.org/10.1101/2020.11.27.401802

ABSTRACT

Chloroplast genes are present at high ploidy in plants, and capable of driving very high levels of gene expression if mRNA production and stability are properly regulated. Marchantia polymorpha is a simple model plant that allows rapid transformation studies, however post-transcriptional regulation in plastids is poorly characterized in this liverwort. We have mapped patterns of transcription in Marchantia chloroplasts. Furthermore, we have obtained and compared sequences from 51 early-divergent plant species, and identified putative sites for pentatricopeptide repeat protein binding that are thought to play important roles in mRNA stabilisation. Candidate binding sites were tested for their ability to confer high levels of reporter gene expression in Marchantia chloroplasts, and levels of protein production and effects on growth were measured in homoplasmic transformed plants. We have produced novel DNA tools for protein hyper-expression in a facile plant system that is a test-bed for chloroplast engineering.