Abstract:

In order to identify and analyze the gene family of ascorbate peroxidase in Prunus salicina, this study used Longzhong as the research material, combined with previously obtained transcriptome data, searched and designed primers using the Chinese plum genome sequence as a template. After PCR, molecular cloning, and sequence analysis verification, six APX genes in Prunus salicina were successfully isolated (PsAPX-1a, PsAPX-1b, PsAPX-1c, PsAPX-1d, PsAPX-1e and PsAPX-1f). An amino acid deletion site on PsAPX-1f was found by NCBI, which prevents PsAPX-1f forming a complete target gene. Submit PsAPX-1a, PsAPX-1b, PsAPX-1c, PsAPX-1d, and PsAPX-1e sequences to GenBank and obtain login numbers PP277487, PP277488, PP277489, PP277490, PP277491 respectively. Multiple sequence alignment revealed that the similarity between PsAPX-1a, PsAPX-1b, PsAPX-1c, PsAPX-1d, and PsAPX-1e ranged from 98.8% to 99.7%. It was found that PsAPX-1a contained a 3' UTR of 79 bp as well as 3 exons and 2 introns, 5' UTR was not included. There was an open reading frame of 1 656 bp encoding 552 amino acids. Protein structure prediction showed that the PsAPX-1a protein had an APX conserved domain, which had high homology with green plum, apricot, and peach. The protein sequence is related to the stress resistance and flowering of Prunus salicina. This study provides a reference for exploring the molecular mechanism of regulating ascorbic acid metabolism in Prunus salicina.

Key words: Prunus salicina, APX gene, gene cloning, sequence analysis