Editing and synthetic engineering of chloroplast genomes

Chloroplasts are central to photosynthesis and metabolic biosynthesis in plants and algae, offering immense potential for synthetic biology. This review highlights recent advances in chloroplast genome minimization, high-efficiency genome editing, and metabolic pathway redesign aimed at optimizing chloroplast function. We first summarize strategies for relocating chloroplast-encoded genes to the nuclear genome, thereby facilitating chloroplast genome streamlining while maintaining gene expression. We then discuss cutting-edge tools for precise chloroplast genome editing, including gene knockout, knockin, base substitution, and multiplex modifications. Finally, we explore the dynamic regulation of chloroplast energy metabolism and the redesign of core metabolic pathways to enable de novo biosynthesis of high-value compounds, enhancing production efficiency and enabling crop trait improvement. Together, these integrated approaches pave the way for next-generation chloroplast engineering with broad implications for biotechnology and agriculture.