FBXO24 functions as a substrate recognition component of the SCF (SKP1-CUL1-F-box protein) E3 ubiquitin ligase complex, mediating proteasomal degradation of multiple target proteins through ubiquitination 1. The protein plays critical roles in spermiogenesis by targeting key proteins including MIWI for K48-linked polyubiquitination and SLC25A26 (mitochondrial S-adenosylmethionine transporter) for K6-linked polyubiquitination, maintaining mitochondrial function and ATP production essential for sperm motility 23. FBXO24 also regulates mRNA alternative splicing by interacting with splicing factors SRSF2, SRSF3, and SRSF9 in round spermatids 2. In cancer biology, FBXO24 functions as a tumor suppressor by targeting oncogenic proteins including LSD1 in breast cancer and facilitating MYC degradation in hepatocellular carcinoma through competition with VRK2-mediated stabilization 45. Additionally, FBXO24 promotes RAD51 degradation via the ATF6-FBXO24 axis, creating BRCAness that sensitizes triple-negative breast cancer to PARP inhibitors 6. FBXO24 also targets mitochondrial aspartyl-tRNA synthetase DARS2 for degradation, modulating immune responses during bacterial infections 1. Clinical significance includes male infertility when deficient and potential therapeutic targeting in cancer treatment.