'Golden rice' is genetically engineered by altering the biosynthetic pathway for the production of
'Golden rice' is genetically engineered by altering the biosynthetic pathway for the production of
Select an option to attempt
Correct Answer: Option A
Explanation
Golden Rice' was developed at ETH Zurich by Ingo Potrykus and Peter Beyer (2000, published in Science). Rationale: rice (Oryza sativa) endosperm lacks-carotene (provitamin A). Genetic modification: Three transgenes introduced into Japonica rice: (1) psy (phytoene synthase) from Narcissus (daffodil) or Zea mays — converts GGPP to phytoene; (2) crtI (carotene desaturase) from Erwinia uredovora (Pantoea ananatis) — converts phytoene to lycopene (4 desaturation steps); (3) lcy(lycopene-cyclase) is already present in rice endosperm (converts lycopene →-carotene). Golden Rice 2 (2005) uses psy from maize, producing 23× more-carotene (37g/g dry weight).-Carotene is a carotenoid (tetraterpene pigment). Not chlorophyll, phycocyanin, or flavonoids.