The Versatile Role of RNA N⁶-Methyladenosine (m⁶A) in Plant Resistance to Biotic Stress

Concerns about biotic stress in agriculture have recently increased with the emergence of persistent pathogens and pests. N⁶-methyladenosine (m⁶A) RNA is a conserved epitranscriptomic modification. Recent advances in plant biotechnology and m⁶A profiling have generated unprecedented knowledge. Our review emphasizes recent state-of-the-art reports regarding m⁶A modulation of plant responses to biotic stress. We found that m⁶A modification plays a "master rheostat" role in plant immunity, potentially integrating signaling, transcription, protein turnover, and global metabolic pathways to achieve vigorous, as well as balanced, responses to biotic stress. This review highlights the potential for m⁶A to dynamically modulate interactions between plant defense hormones and defense pathways. m⁶A modulates the stability and activity of transcription factors, regulates defense proteins, antimicrobial metabolite production, antiviral defense, systemic acquired resistance, and the ubiquitin-proteasome pathway. Our review examines contextual factors that coordinate the activity of m⁶A-associated proteins and modulate global m⁶A dynamics. Importantly, we have addressed m⁶A in the context of promising trade-offs between defense and growth, and in the role of m⁶A-associated proteins in liquid-liquid phase separation to control hormonal transcript levels and fine-tune the plant defense response. Overall, this review proposes a new horizon for developing more biotic-stress-resilient plants.