Plant RNA Pol Ⅳ/Ⅴ: structural-functional insights and pedagogical applications

Eukaryotic RNA polymerases Ⅳ (Pol Ⅳ) and Ⅴ (Pol Ⅴ) are core enzymes in the plant specific RNA-directed DNA methylation (RdMM) pathway, mediating important epigenetic regulatory processes. The current molecular biology textbooks lack sufficient introduction to it, which limits students' deep understanding of the field. Based on the latest advances in structural biology, such as the synergistic assembly of RNA Pol Ⅳ with RDR2, and the transcriptional stalling mechanism of RNA Pol Ⅴ, this paper systematically elucidates their subunit composition, structural characteristics, and functional specialization. Furthermore, grounded in the principles of constructivism and evidence-based teaching, we proposed a conceptual scaffold and a scientific narrative method to update the textbook content. We also introduced teaching methods such as visual analysis, role simulation, and case study to construct a teaching paradigm for the collaborative cultivation of knowledge ability literacy. This work offers a systematic solution to bridge the gap between cutting-edge disciplines and classroom teaching, and provides a reference paradigm for the reform of molecular biology courses and the cultivation of innovative talents in agricultural and forestry universities.