Post-transcriptional regulation comprises the molecular processes that control the maturation, molecular fate, abundance, localization, and functional output of RNA molecules after their synthesis. In protein-coding gene expression, it encompasses RNA processing events—including 5′-end capping, splicing, editing, and 3′-end cleavage and polyadenylation—as well as nuclear export, subcellular localization, translational control, RNA surveillance, and degradation. These regulatory activities operate through cis-acting RNA sequence and structural elements, RNA chemical modifications, and trans-acting factors such as RNA-binding proteins, regulatory non-coding RNAs, RNA-processing enzymes, and ribonucleoprotein complexes ^[1][2][3]. By determining which RNA isoforms persist, where they accumulate, how long they remain available, and the extent to which they are translated, post-transcriptional regulation establishes RNA-specific and context-dependent patterns of gene expression ^[1][2].