ID 1.3.1.90 DE tRNA-dihydrouridine(20a/20b) synthase [NAD(P)(+)]. CA (1) 5,6-dihydrouridine(20a) in tRNA + NADP(+) = H(+) + NADPH + CA uridine(20a) in tRNA. CA (2) 5,6-dihydrouridine(20a) in tRNA + NAD(+) = H(+) + NADH + uridine(20a) CA in tRNA. CA (3) 5,6-dihydrouridine(20b) in tRNA + NAD(+) = H(+) + NADH + uridine(20b) CA in tRNA. CA (4) 5,6-dihydrouridine(20b) in tRNA + NADP(+) = H(+) + NADPH + CA uridine(20b) in tRNA. CC -!- The enzyme specifically modifies uracil(20a) and uracil(20b) in tRNA. DR O95620, DUS4L_HUMAN; Q32M08, DUS4L_MOUSE; O74553, DUS4_SCHPO ; DR Q06063, DUS4_YEAST ; //