Control of chloroplast biogenesis by MYB-related transcription factors

In this study, Frangedakis et al. identified MYB-related transcription factors as critical regulators of chloroplast development in land plants. Focusing on the liverwort Marchantia polymorpha and the angiosperm Arabidopsis thaliana, the team discovered that mutations in some MYB-related genes lead to pale plant phenotypes with significantly smaller chloroplasts, indicating their pivotal role in chloroplast biogenesis. Through genetic analysis and gene editing, the study revealed that these transcription factors target a broad array of genes involved in various aspects of chloroplast function, including chlorophyll biosynthesis, carbon fixation, photorespiration, and the assembly and repair of photosystems.  The research also revealed that these MYB-related transcription factors work redundantly and synergistically with other known regulators, such as the GOLDEN2-LIKE (GLK) family of transcription factors, to control chloroplast development. This discovery not only reveals the regulatory mechanisms governing chloroplast development but also opens new avenues for enhancing crop productivity by manipulating these master regulators. (Summary by Amarachi Ezeoke) Cell 10.1016/j.cell.2024.06.039