The jasmonic acid-responsive transcription regulator TIFY25 modulates the expression of the age biomarker DAL1 in...

The age-regulation mechanism plays a crucial role throughout the entire life cycle of plants, including vegetative growth, growth phase transition, reproductive development, senescence, and regeneration. While this mechanism has been elucidated in angiosperms, it remains poorly understood in gymnosperms. DEFICIENS AGAMOUS-LIKE 1 (DAL1) is a conserved age biomarker in gymnosperms that integrates the aging pathway and reproductive development. However, the molecular regulatory mechanisms governing DAL1 expression patterns are not well understood. In this study, we revealed that DAL1 can activate its own expression through a positive feedback loop by directly binding to its own promoter region. Furthermore, the jasmonic acid (JA)-responsive transcriptional regulator TIFY25 acts as a 'brake' by directly interacting with DAL1 via protein-protein interactions. This interaction inhibits the self-activation of DAL1, ensuring that its expression increases gradually and steadily with age, thereby preventing premature or excessive activation. These findings provide insights into the age-regulation mechanism and integrate JA into the age pathway in P. tabuliformis.