Molecular basis of polyadenylated RNA fate determination in the nucleus

Researchers identified the molecular mechanism determining the fate of polyadenylated RNA in the nucleus on June 17, 2026. Biochemical, structural, and cell biological analyses published in Nature revealed that the protein UAP56, also known as DDX39B, forms a complex with a TREX-2-like module. This assembly redirects non-functional polyadenylated RNAs away from export pathways and directs them towards degradation. This finding clarifies a critical step in cellular RNA management, ensuring that only functional RNAs are processed for downstream cellular functions. The study utilized advanced imaging and biochemical assays to visualize and characterize the protein complex and its interaction with RNA molecules. Understanding this process is crucial for comprehending gene expression regulation and cellular homeostasis, with potential implications for diseases linked to RNA processing errors.