Work

PbrIDD2 ‐ PbrAPX14 Module Functions in the Ethylene‐Mediated Ripening and Senescence Process of Pear Fruit

Year: 2026

Type: article

Abstract: ABSTRACT Endogenous H 2 O 2 participated in the ethylene‐dependent ripening and senescence process of horticultural fruit as a secondary messenger; however, the molecular mechanism beneath such a phenomenon has not been fully clarified until recently. By a conjoint analysis of metabolite, enzyme activities, gene expression profiles in AsA‐GSH cycle of ‘Kolar’ pear, PbrAPX14 might act as a negative factor in the ethylene‐mediated H 2 O 2 accumulation. PbrAPX14, located in cytosol, would reduce H 2 O 2 in vitro and in vivo, inhibit ethylene production, and thus fruit ripening and senescence. After analysing the expression profiles of the differentially expressed transcription factors (TFs) followed by experimental validation, the nuclear PbrIDD2 could directly bind to the cis ‐acting element (core motif: TTTGTCG) in PbrAPX14 promoter, activate its expression and thus enhance the H 2 O 2 ‐scavenging capacity of fruit/calli, which was associated with the mitigated ethylene evolution and fruit ripening and senescence. Further study explored that the H 2 O 2 ‐mediated post‐translational S‐sulfenylation of Cys 48 residue in PbrAPX14, which mitigated its function, existed in vitro and in vivo, and was upregulated by ethylene, facilitating endogenous H 2 O 2 accumulation. Overall, our results implied that both transcriptional and post‐translational regulation of PbrAPX14, which were (in)directly under the control of ethylene, functioned in pear ripening and senescence process via regulating endogenous H 2 O 2 level.

Source: Plant Biotechnology Journal

DOI: 10.1111/pbi.70664