A citrus pulp mastication trait-related ABSCISIC ACID-INSENSITIVE 5-like protein promotes fruit softening via transcriptionally activating pectate lyase gene

•A “ABSCISIC ACID-INSENSITIVE 5-like protein” (named CsABI5-L) high expressed in the citrus cultivar with superior mastication trait.•CsABI5-L was homologous with Arabidopsis AtbZIP36/AtABF2.•CsABI5-L is a transcription factor confirmed by subcellular localization.•CsABI5-L-overexpressing tomato lines showed decreased firmness compared with the wild type.•A specific binding of CsABI5-L to the tomato SlPL promoter was demonstrated by dual-luciferase transient expression assay.