Cloning and expression of genes involved in anthocyanins synthesis in ornamental sunflower.

Six structural genes(PAL,CHS,CHI,F3'H,DFR,ANS)involved in anthocyanins synthesis were cloned from the ray florets of ornamental sunflower(Helianthus annuus L.)by homology sequence cloning.Sequence analysis showed that these genes shared high similarity with genes from other plants,ranging from 95%-97%,83%-99%,64%-80%,80%-82%,64%-85% and 87%-89%,respectively.The results of phylogenetic analysis were in agreement with that described in plant taxonomy.Semi-quantitative RT-PCR indicated that the transcripts of all six genes were detected in ray florets,tubular florets,buds,leaves,and barks except that the transcript of CHS was not detected in tubular florets.Expression levels of most structural genes were higher in first florescence and full bloom periods and then decreased.The transcripts of these genes were higher in purple petals than in chocolate petals,and higher in petal with deep color than with multi-color.