Abstract: The mRNA sequence for Capsanthin/Capsorubin synthase (CCS) has been cloned from fruits of Newhall navel orange by RT-PCR. Sequencing results revealed that it was 1 619 bp in length, encoding 503 amino acids. BLAST results showed that the deduced amino acids shared the same amino acid sequence as that of Citrus sinensis, 70% identities with CCS of Daucus carota and Capsicum annuum. In addition to 70% identities with neoxanthin synthase (NSY) of Solanum tuberosum, it showed 50%~70% identities with lycopene cyclase of Lycopersicon esculentum and citrus. Semi-quantitative RT-PCR results showed that expressions of Ccs were down-regulated during fruit ripening of Newhall navel orange, with the highest one in September.

Key words: RT-PCR, citrus, Capsanthin/Capsorubin synthase, gene