Scientists have identified a protein, Lipid Remodeling reguLator 1 (LRL1), in microscopic algae that is involved in the production of triacylglycerol, a biofuel precursor. They further reveal additional proteins and biochemical pathways that contribute to the production of this precursor, and show that the protein particularly functions by limiting phosphorus in the environment. Their results could help develop new methods to improve the efficiency of biofuel production from microalgae.