板栗PPO基因克隆及生物信息学分析.

[Objective] The present paper aimed to study the function of PPO gene related to heat browning chestnut kernels metabolic mechanism.【Method】A PPO unigenes was obtained from transcriptome data based on transcriptome sequencing and bioinformatics analysis. [Result] The full length of open reading frame was 1794 bp，belonged to the PPO gene family，named CmPPO, encoding 597 amino acids with a molecular weight of 66 335. 38, containing the (common central region and the (conserved intermediate domain of the PPO, which had a theoretical pl of 6.45, including common central domain of tyrosinase and PPO middle binding domain. The secondary structure of the CmPPO protein contained 21.22% alpha-helix, 59.13% random coils, 15.91% extended strands and 3.85% beta-turns. The three-dimensional structure of the CmPPO protein was similar to apple complexase (MdPPO1), sequence identity was 72.75%, sequence similarity was 53%, and amino acid sequence identity was 68.43%, suggesting that they had similar functions. Based on RT-PCR, the expression of CmPPO gene in difference cultivated varieties and tissues of chestnut kernels was different from the degree of fruit browning, but the highest expression was found in weak browning varieties. [Conclusion] This indicated that the browning was not controlled by single gene, but by multiple genes and metabolic pathways. [ABSTRACT FROM AUTHOR]