DEAH ‐Box RNA Helicases in the Spliceosome: Advances in Structure and Function

Pre‐mRNA splicing is orchestrated by the spliceosome through coordinated RNA and protein rearrangements driven by ATP‐dependent RNA helicases. DEAH‐box helicases serve as principal motors, controlling catalytic activation, exon ligation, and complex disassembly. Early mechanistic understanding was limited by low‐resolution cryo‐electron microscopy (cryo‐EM) structures, leaving RNA substrate interactions largely inferred from biochemical and genetic studies. Recent high‐resolution cryo‐EM structures (2021–present) have captured all five spliceosomal DEAH‐box helicases—DHX16/Prp2, DHX38/Prp16, DHX8/Prp22, DHX15/Prp43, and DHX35—bound to their RNA targets within distinct spliceosomal states. These structures reveal precise recruitment, substrate recognition, and stage‐specific actions. In this review, I integrate these insights into a unified framework, highlighting structural, biochemical, and evolutionary perspectives to guide future investigations of helicase regulation and their role in maintaining the fidelity of eukaryotic RNA splicing.