Cloning and Expression of Phytoene Desaturase Gene, PpPDS, from Peaches

The full-length cDNAs of phytoene desaturase (PDS) from peaches was isolatedby gene cloning, and named as PpPDS. It was 2 056 bp in length and encoded a predicted protein of 573 amino acids (ORF length at 1 722 bp). A phylogenetic analysis indicated that PpPDS closely resembled the PDSs from Prunus armeniaca and Fragaria×ananassa. The deduced amino acid sequence suggested that PpPDS protein contained dinucleotide binding motifs, NAD (H), NADP (H) or FAD (H), which belonged to the NAD(P)-binding rossmann-like conserved domain. Quantitative real-time PCR showed that PpPDS gene was generally expressed higher in mesocarp than exocarp in fruits of Jinli yellow peach at different maturity stages. After the peach stone hardened, the gene expression increased significantly, then leveled off at the peak. The information would be useful for further studies on the carotenoid biosynthesis pathway in peaches.