Oryza sativa sprang from a single domestication that occurred 8,200–13,500 years ago in China of the wild rice "Oryza rufipogon". A 2012 study, through a map of rice genome variation, indicated that the domestication of rice occurred in the Pearl River valley region of China. From East Asia, rice was spread to South and Southeast Asia. Before this research, the commonly accepted view, based on archaeological evidence, is that rice was first domesticated in the region of the Yangtze River valley in China. The precise date of the first domestication is unknown, but depending on the molecular clock estimate, the date is
12-oxophytodienoate reductase 12-oxophytodienoate reductase 12-oxophytodienoate reductase (OPRs) is an enzyme of the family of Old Yellow Enzymes (OYE). OPRs are grouped into two groups: OPRI and OPRII – the second group is the focus of this article, as the function of the first group is unknown, but is the subject of current research. The OPR enzyme utilizes the cofactor flavin mononucleotide (FMN) and catalyzes the following reaction in the jasmonic acid synthesis pathway: This reaction occurs in peroxisomes in plants. Several isozymes have been discovered, with varying substrate stereospecificity: three in "Lycopersicon esculentum", 13 in "Oryza sativa", and five in "Arabidopsis thaliana".