Activities | Families | Sequences | Fold types | References | Help
B6db references: 99196994

type Journal Article
authors Nakamura, T.; Yamaguchi, Y.; Sano, H.
title Four rice genes encoding cysteine synthase: isolation and differential responses to sulfur, nitrogen and light
journal Gene
Activity 2.5.1.47
ui 99196994
year (1999)
volume 229
number 1-2
pages 155-61.
 
keywords Amino Acid Sequence
abstract Four cDNA clones, rcs1, rcs2, rcs3 and rcs4, encoding cysteine synthase [O-acetylserine(thiol)lyase] were isolated from rice. The predicted amino acid sequences contain the conserved PXXSVKDR region characteristic of cysteine synthase, which includes the lysine residue that binds the cofactor, pyridoxal 5'-phosphate. Molecular phylogenic analysis suggests that, whereas rcs1 and rcs3 belong to the cytosolic isoform family, rcs2 and rcs4 form a new family of cysteine synthase. Transcript accumulation of each gene was examined for organ specificity, and also for response to sulfur, nitrogen and light. The rcs1 transcript accumulated in all organs examined, and was induced in shoots and roots upon sulfur starvation under non-limiting nitrogen conditions. The rcs2 transcript accumulated in shoots grown in the light, but disappeared almost completely by dark treatment. The rcs3 transcript was found more abundantly in roots than in shoots, and was reduced in the dark, as well as under sulfur and nitrogen deprivation. The rcs4 transcript was scarce in all organs examined. These observations indicate that cysteine synthase genes encode functionally distinct cysteine synthase isoforms, and that they are coordinately regulated by the availability of sulfur, nitrogen, and light.
last changed 2003/03/17 14:53

B6db references