Abstract: In order to explore the role of mango PAO gene in the degradation of chlorophyll in mango peel,we used PAO partial fragments some from transcriptome sequencing to design primers,3' and 5' rapid-amplification of cDNA ends(RACE) was adopted,three different colored mango varieties,red Guifei,yellow Jinhuang and green Guiqi,were selected as experimental materials,and finally the full-length cDNA sequences of PAO genes in mango pericarp were cloned. It was named MiPAO by bioinformatics analysis. The results showed that only a few bases group differences in the MiPAO genes cDNA sequences of three different colored mango varieties. For example,the full-length cDNA of MiPAO was 1 979 bp length,its open reading frame (ORF) was 1 641 bp,encoding a protein of 546 amino acids,with a predicted molecular weight of 61.82 ku,the isoelectric point of the predicted protein was 6.54 in red Guifei mango. Secondary structure and three kinds of tertiary structure diagram of MiPAO protein were obtained by the prediction of biological software. It was found that the gene encoding for the protein had close relationship with orange by other plants through phylogenetic analysis. It successfully constructed pTRV₂-MiPAO gene silencing vector. In order to support for the color formation and color regulation of mango fruits during ripening. It also provided some experimental support for the reasons for the stay-green of the Guiqi mango.

Key words: Mango, MiPAO, Chlorophyll degradation, Virus-induced gene silencing

CLC Number: 

• Q78

• S667.03