Anthurium Flowers PAL Gene Cloning And Anthocyanin Content

PAL is the starting enzyme in the pathway of anthocyanin biosynthesis and the color of Anthurium andraeanum spathes was mainly consisted of anthocyanins. So far, few researchs about the relationship between PAL and anthocyanin synthesis of Anthurium andraeanum was reported. Here, the full-length PAL cDNA of Anthurium andraeanum were cloned with "Arizona" as materials and studied by RT-PCR and Real-time PCR.Ethylene can promote the synthesis of anthocyanins. In order to study the effect and the control of PAL gene and ethylene treatment on the coloration of Anthurium andraeanum Spathe, Anthurium andraeanum spathe was processed by ethephon, the gene expression of Anthurium andraeanum spathes were studied by Real-time PCR, and the content of anthocyanin and total flavonoid was detected at five different concentrations of ethephon treatment in Anthurium andraeanum Spathe by means of high performance liquid chromatography (HPLC) with direct injection and gradual elution, and determination of enzyme activity of related enzymes.The results showed that:(1). The cDNA sequence of PAL gene fragment which was about300bp long was cloned from Anthurium "Arizona" Spathe by using a pair of degenerate primers. According to this sequence fragment, the primers for3'and5'rapid-amplification of cDNA ends (RACE) were designed to clone the3'and5'end cDNA sequences of PAL gene by RACE method. The full-length PAL cDNA was got, through splicing,2461bp with poly(A) tailing and containing a2013bp open reading frame (ORF) encoding a671amino acid protein.Through bioinformatic analysis, found that PAL speculated that the molecular weight of Anthurium72458.8Da, isoelectric point is6.02, not membrane proteins. Discovered through multiple nucleotide and protein sequence comparison, anthurium andraeanum PAL gene highly homologous with other plants, PAL phylogenetic tree shows that in monocots and PAL gene cluster recently. Anthurium andraeanum PAL was found to have extensive homology with those of other plants via multiple alignments. Phylogenetic tree analysis revealed that anthurium andraeanum PAL had closest relationship with PALs from monocots.(2). Highest of PAL gene expression in the Anthurium andraeanum spathe, which late for anthocyanin synthesis provides plenty of precursor substances; PAL gene expression was increased of Anthurium andraeanum spathes by ethephon.(3). The anthocyanin of Anthurium andraeanum 'Arizona' was mainly composition of cyanidin-3-o-rutinoside chloride. It can induced PAL gene expression and promote the synthesis of anthocyanins and flavonoids of Anthurium andraeanum spathe by ethephon. The highest peak of the content of anthocyanins and total flavonoids was appeared in the600mg/L ethephon treatment.(4). All of POD, PPO and PAL activity are on the rise of Anthurium andraeanum spathe by ethephon, and the highest peak of enzyme activity was appeared in the600mg/L ethephon treatment. POD and PAL activity of enhancing the promotion of anthocyanin synthesis, but there was no correlation between anthocyanin content changes and PPO activity.