Exploring ABI5 regulation: Post‐translational control and cofactor interactions in ABA signaling

SUMMARY Abscisic acid insensitive 5 (ABI5) is a pivotal transcription factor in abscisic acid (ABA) signaling, playing an essential role in plant growth and responses to abiotic stress. This key regulator is subject to multifaceted regulation, especially on post‐translational mechanisms. Recent research has shed light on the post‐translational regulation of ABI5, encompassing both post‐translational modifications (PTMs) and the modulation of its transcriptional activity. In this review, we provide a comprehensive overview of the current knowledge surrounding the post‐translational regulation of ABI5, along with the influence of various cofactors on its transcriptional activity and protein stability. The potential biological roles of PTMs of ABI5 in the context of ABA signaling and plant stress responses are also explored. As ABI5 is one of the most extensively studied proteins in the context of plant ABA signaling and environmental stress responses, a sophisticated and precise understanding of the regulatory mechanisms that govern ABI5 is not only beneficial for its application in genetic engineering but also helpful for our exploration in the fundamental principles of post‐translational regulation.