LIL3, a light-harvesting complex protein, links terpenoid and tetrapyrrole biosynthesis

The final step in the synthesis of chlorophyll is the joining of chlorophyllide, (a tetrapyrrole with planar structure similar to heme) to a linear lipid (a product of the terpenoid pathway) that provides an attachment point for the resulting chlorophyll to pigment-binding proteins of the light-harvesting complexes. LIL3 (Light-harvesting-Like) is a membrane-spanning protein that was previously shown to interact with geranylgeranylreductase (CHLP), an enzyme involved in terpene biosynthesis. Hey et al. show that LIL3 also interacts with protochlorophyllide oxidoreductase (POR), the enzyme that catalyzes chlorophyllide production, as well as its substrate, protochlorophyllide. The authors suggest that through these interactions, LIL3 may serve to coordinate the production of the two intermediates required for chlorophyll production. Plant Physiol. 10.​1104/​pp.​17.​00505