Myb-Like Transcription Factor Nopsr1 Is Crucial For Membrane Lipid Remodeling Under Phosphate Starvation In The Oleaginous Microalganannochloropsis Oceanica

Membrane lipid remodeling under phosphate (Pi) limitation, a process that replaces structural membrane phospholipids with nonphosphorus lipids, is a widely observed adaptive response in plants and algae. Here, we identified the transcription factor phosphorus starvation response 1 (NoPSR1) as an indispensable player for regulating membrane lipid conversion during Pi starvation in the microalgaNannochloropsis oceanica. Knocking outNoPSR1scarcely perturbed membrane lipid composition under Pi-sufficient conditions but significantly impaired dynamic alteration in membrane lipids during Pi starvation. In contrast, the absence ofNoPSR1led to no obvious change in cell proliferation or storage lipid accumulation under either nutrient-sufficient or Pi-deficient conditions. Our results demonstrate a key factor controlling the membrane lipid profile during the Pi starvation response inN. oceanica.