Oryza sativa estimated to be 8,200 to 13,500 years ago. This is consistent with known archaeological data on the subject. An older theory, based on one chloroplast and two nuclear gene regions, Londo "et al." (2006) had proposed that "O. sativa" rice was domesticated at least twice—"indica" in eastern India, Myanmar, and Thailand; and "japonica" in southern China and Vietnam—though they concede that archaeological and genetic evidence exist for a single domestication of rice in the lowlands of China. Because the functional allele for nonshattering, the critical indicator of domestication in grains, as well as five other single-nucleotide polymorphisms, is identical in
Arogenate dehydratase hybrida", "Sorghum bicolor"", "and "Oryza sativa"", "which are all considered higher-order plants. "Erwinia herbicola"" and Pseudomonas aeruginosa"" "are known to" "have homologues for cyclohexadienyl dehydratase. Of the plants with ADT homologues, both "Arabidopsis thaliana "and "Petunia hybrida "are known to have paralogues for the gene (six and three, respectively). Arogenate dehydratase Arogenate dehydratase (ADT) (EC 4.2.1.91) is an enzyme that catalyzes the chemical reaction Hence, this enzyme has one substrate, L-arogenate, but 3 products:L-phenylalanine, HO, and CO. Certain forms of the protein have the potential to catalyze a second reaction, L-prephenate → L-phenylpyruvate + HO + CO This enzyme participates