EIF4A2 is an ATP-dependent RNA helicase and subunit of the eIF4F complex essential for translation initiation 1. It unwinds 5'-UTR secondary structures to facilitate ribosomal scanning and mRNA binding 2. EIF4A2 functions as a key regulatory node in microRNA-mediated translational repression, where it is targeted by miRNAs to inhibit translation of specific mRNAs—this translational inhibition precedes mRNA degradation 2. In stem cells, eIF4A2 selectively activates translation of pluripotency factors and histone H3.3, maintaining ESC identity 3. Beyond development, eIF4A2 is recruited by RNA-binding proteins to enhance translation of specific oncogenic transcripts; for example, RBM12 recruits eIF4A2 to increase JAK1 mRNA translation in hepatocellular carcinoma, driving PD-L1 immune evasion 4. Similarly, in acute myeloid leukemia, eIF4A2 enrichment in leukemic stem cells supports their maintenance 5. In cardiac metabolism, H19 lncRNA inhibits Pink1 mRNA translation by blocking eIF4A2 binding, thereby suppressing mitophagy 6. Clinically, EIF4A2 haploinsufficiency causes dominant-inheritance dystonia with tremor onset in adolescence-to-adulthood, linked to translational dysregulation of microRNA-target genes like IMP1 7. EIF4A2 mutations are also associated with neurodevelopmental disorders featuring hypotonia and speech delay with or without seizures.