Advances in the transcriptional regulation and lipid droplet turnover in microalgae

Microalgae have garnered significant research interest due to their potential to utilize CO₂ for the production of lipids, especially as a source of high-value lipids. The biosynthesis, accumulation, and turnover of lipid droplets in microalgae constitute a complex metabolic process. While the lipid synthesis pathways in algal cells are relatively well understood, research on lipid droplet transport, turnover, and related regulatory mechanisms is still limited. This review summarizes the mechanisms by which transcription factors regulate lipid accumulation in microalgae, based on the latest progress, and delves into the spatial locations of lipid droplet synthesis and degradation. Special attention is given to the process of lipid droplet turnover, encompassing lipid droplet formation, lipid droplet transport, and the initiation of lipolysis. A comprehensive understanding of these processes is essential for optimizing microalgal strains to enhance lipid production and fully harness the potential of microalgae as a sustainable source of bioenergy and specialty lipids.