Liquid-liquid phase separation of transcription factors facilitates environmental adaptation in plants

Liquid-liquid phase separation (LLPS) has emerged as a crucial mechanism for transcriptional regulation in plants, enabling the dynamic compartmentalization of biomolecular condensates. These condensates orchestrate gene expression by modulating the spatiotemporal distribution of transcription factors, allowing plants to cope with fluctuating environments. Recent studies have revealed 2 distinct LLPS-driven modes in plants. In the activation mode, transcription-factor condensates assemble transcriptional hubs enriched in RNA polymerase II and coactivators, accelerating target-gene recognition through localized molecular crowding. In the repression mode, condensates sequester repressors, thereby blocking transcription at target loci or segregating transcription factors from transcriptionally active chromatin. This functional dichotomy supports a rheostat-like model in which plants fine-tune condensate composition and material properties to balance stress adaptation with development by controlling condensate accessibility at promoters and other regulatory loci. Here, we propose a dual-model framework that explains how transcription-factor condensates mediate environmental adaptation in plants involving exclusion-sequestration and aggregation-enrichment mechanisms with a focus on Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa). This conceptual framework provides a theoretical basis for dissecting the transcriptional networks that underlie environmental responsiveness in plants.