DDX19A is an ATP-dependent RNA helicase that plays a crucial role in mRNA nuclear export by functioning as a ribonucleoprotein particle remodeler rather than a traditional RNA duplex unwinder 1. The protein operates at the cytoplasmic side of the nuclear pore complex, where it removes nuclear RNA-binding proteins from mRNPs and facilitates their replacement with cytoplasmic mRNA-binding proteins to terminate mRNP export 1. DDX19A's function is regulated by SUMOylation at lysine 26, which enhances its interaction with the cofactor Gle1 and is essential for proper mRNA export activity 1. Beyond its primary export function, DDX19A serves as a transcriptional coregulator that binds H3K27me3 and regulates gene expression through R-loop removal, participating in a feedback loop with LSD1 and PRC2 for gene silencing 2. The gene exhibits clinical significance as it modulates selinexor sensitivity in leukemia cells by regulating MCL1 mRNA nuclear export, suggesting potential as a therapeutic biomarker 3. DDX19A is also downregulated in ovarian cancer and targeted by let-7b-5p, indicating tumor suppressor functions in certain contexts 4. The gene has undergone concerted evolution with its paralog DDX19B for over 100 million years, maintaining functional redundancy 5.