In a groundbreaking development, researchers in China have reached a significant milestone in the synthesis of an artificial genome for a multicellular organism, specifically a type of moss known as spreading earthmoss (Physcomitrium patens). Published last week in Nature Plants, the accomplishment not only represents a crucial step toward generating fully artificial plant genomes but also opens avenues for utilizing moss as a potential factory for producing medicines and other valuable products.
While previous synthetic genomic projects focused on bacteria and yeast, this venture delves into the realm of multicellular organisms. The Chinese team, led by synthetic biologist Junbiao Dai and developmental biologist Yuling Jiao, targeted a segment of chromosome 18 in spreading earthmoss, marking progress toward a complete artificial plant genome. Ian Ehrenreich from the University of Southern California emphasizes that this work is essential for understanding the fundamental aspects of genome organization and function in plants.
Unlike the yeast project, which primarily deals with single-cell organisms, the choice of moss as the subject organism offers unique advantages. A single moss cell can develop into an entire plant, simplifying the engineering process. Additionally, the moss exhibits a higher frequency of a crucial DNA-swapping process compared to other model plants.
Named SynMoss, the project began by modifying part of the short arm of chromosome 18, involving the elimination of transposons, the addition of genetic code labels, and other optimizations. The resulting partly synthetic structure was successfully introduced into individual moss cells, leading to the growth of normal-looking plants. These modified moss plants demonstrated resilience to environmental stresses, maintaining their size, shape, and reproductive capabilities.
However, the study revealed that some genes in the synthetic region exhibited increased activity, suggesting potential challenges. This finding adds to the ongoing debate regarding the essential role of transposons in multicellular eukaryotes.
The significance of this achievement extends beyond fundamental research, as spreading earthmoss has already been harnessed for the production of certain chemicals, including drugs undergoing clinical trials. The project, according to plant biologist Ralf Reski, paves the way for more extensive and impactful modifications to the moss genome.
Looking ahead, the ambitious goal of completing the entire synthetic moss genome within the next 10 years reflects the researchers' commitment to advancing the field of synthetic genomics. The scale of this endeavor, considering the moss genome's size compared to yeast, underscores the complexity and challenges associated with creating artificial genomes for multicellular organisms.
More: https://www.science.org/content/article/moss-project-takes-step-toward-first-artificial-plant-genome
