Identification and Expression Pattern of a Novel NAM, ATAF, and CUC-Like Gene from Citrus sinensis Osbeck

A citrus NAM, ATAF, and CUC (NAC)-like gene (CitNAC) was isolated from fruit tissues of Citrus sinensis Osbeck using complementary DNA (cDNA) amplified fragment length polymorphism and rapid amplification of cDNA ends techniques. Its full length was 988 bp in which 781 bp form the open reading frame, coding for a protein of 264 amino acids. Sequence comparison revealed that CitNAC possesses the general structural features at the N terminus of the NAC domains. Phylogenetic analysis results showed that CitNAC was closely related to AtNAP and PeNAP, which are involved in plant organ senescence. Gene expression analysis showed that the messenger RNA level of CitNAC was just detected in fruit peel and pulp during fruit ripening or senescence stage. The observed expression pattern of CitNAC along with the result of phylogenetic analysis suggested that CitNAC is related to fruit development and senescence.