ACTR2 (actin-related protein 2) is an ATP-binding component of the Arp2/3 complex that nucleates branched actin filament networks essential for cellular motility 1. Beyond its canonical cytoplasmic role in lamellipodia formation and cell migration, ACTR2 participates in nuclear actin polymerization regulating transcription and DNA repair 23. The protein promotes homologous recombination repair by facilitating nuclear actin polymerization and double-strand break motility 3. In oocyte meiosis, ACTR2 maintains proper spindle assembly and cortical positioning through autophagy regulation 4. ACTR2 expression is transcriptionally regulated by YAP/TAZ mechanosignaling and contributes to nuclear envelope integrity via the perinuclear actin cap 5. Disease relevance spans multiple conditions: ACTR2 is differentially expressed in recurrent pregnancy loss and miscarriage, with studies identifying it as a potential therapeutic target 67. Genetic variants near ACTR2 associate with calcific aortic stenosis susceptibility through effects on dyslipidemia and inflammation pathways 8. In bladder cancer, elevated ACTR2 expression promotes pseudopodia formation and metastasis through actin nucleation 9. ACTR2 upregulation during human oocyte maturation suggests roles in meiotic progression 10. These findings establish ACTR2 as a multifunctional cytoskeletal regulator with implications for reproductive health, cardiovascular disease, and cancer metastasis.