AUTHOR=Song Jianfei , Yang Fei , Xun Mi , Xu Longxiao , Tian Xiaozhi , Zhang Weiwei , Yang Hongqiang 

TITLE=Genome-Wide Identification and Characterization of Vacuolar Processing Enzyme Gene Family and Diverse Expression Under Stress in Apple (Malus × Domestic)

JOURNAL=Frontiers in Plant Science

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2020.00626

DOI=10.3389/fpls.2020.00626

ISSN=1664-462X

ABSTRACT=<p>Vacuolar processing enzymes (VPEs) play an important role in stress resistance and development of plants. Despite their diverse roles, little information is available in apple (<italic>Malus</italic> × <italic>domestic</italic>). This study firstly presents the genome-wide identification of VPE family genes in apple, resulting in 20 family members those are unevenly distributed across six out of the 17 chromosomes. Phylogenetic analysis assigned these genes into four groups. Analysis of exon–intron junctions and motifs of each candidate gene revealed high levels of conservation within and between phylogenetic groups. <italic>Cis</italic>-element including w box, ABRE, LTR, and TC-rich repeats were found in promoters of <italic>MdVPEs</italic>. NCBI-GEO database shown that the expression of <italic>MdVPEs</italic> exhibited diverse patterns in different tissues as well as the infection of <italic>Pythium ultimum</italic> and <italic>Apple Stem Grooving Virus</italic>. Furthermore, qRT-PCR showed that <italic>MdVPE</italic> genes were responsive to salt, cadmium, low-temperature, and drought. Overexpression of MDP0000172014, which was strongly induced by salt and drought stress, significantly decreased <italic>Arabidopsis</italic> tolerance to salt stress. The genome-wide identification and characterization of <italic>MdVPEs</italic> in apple provided basic information for the potential utilization of <italic>MdVPEs</italic> in stress resistance.</p>