Abstract
Higher plants have two metabolic pathways for isoprenoid biosynthesis: the cytosolic mevalonate (MVA) pathway and the plastidal non-mevalonate pathway. Little is known about the mechanisms that regulate the two pathways and the metabolic cross-talk. We isolated and characterized the Arabidopsis T-DNA insertion mutant lovastatin insensitive 1 (loi1), which is resistant to lovastatin, an inhibitors of the MVA pathways. LOI1 encodes a novel PPR protein and located in mitochondria. PPR proteins are known to function as RNA editing and post-transcriptional regulation of organelle DNA. We identified a substrate RNA of LOI1 protein by both SELEX method and in vivo binding assay. The substrate was a transcript of COX3, one of the elements of respiration chain. In this symposium, I will discuss on molecular dynamism of respiration chain and isoprenoid biosynthesis regulated by LOI1.
