Isolation and characterization of carotenoid cleavage dioxygenase genein halophyte Suaeda salsa

摘要

A full-length cDNA of SsCCD1 gene encoding carotenoid cleavage dioxygenase was isolated from a halophyte Suaeda salsa. Sequence analysis revealed that SsCCD1 shares a high homology with AtCCD1 from Arabidopsis thaliana. The 1972 bp full-length SsCCD1 has an open reading frame of 1677 bp and encodes a 62.5 KDa protein, with 5'- and 3'-untranslate region of 72 bp and 229 bp, respectively. Northern blotting analysis indicated that the SsCCD1 mRNA levels were significantly up-regulated by NaCl and drought stresses in both root and aerial part tissues. High temperature and ABA also increased the transcriptional level of SsCCD1. Transgenic arabidopsis with overexpression of SsCCD1 gene did not show an increased endogenous ABA concentration, but decreased the carotenoid concentration, indicating that CCD enzyme may be involved in the carotenoid catabolism.