MED24 is a component of the Mediator complex, a coactivator essential for regulated transcription of RNA polymerase II-dependent genes. It functions as a scaffold bridging gene-specific regulatory proteins to the basal transcription machinery and facilitates preinitiation complex assembly 1. MED24 operates through direct functional communication with other Mediator subunits; specifically, MED24-containing submodules cooperate with MED1 to mediate estrogen receptor functions in mammary gland development and breast carcinoma cell growth 1. Beyond transcriptional regulation, MED24 participates in steroid hormone-triggered programmed cell death, with Drosophila studies showing Med24 mutations block salivary gland cell death during metamorphosis through mechanisms independent of death regulator gene expression 2. Clinically, MED24 dysregulation associates with multiple malignancies: it is an ERBB2 downstream oncogenic target in lung cancer development 3, shows elevated expression correlating with poor prognosis and immune infiltration in hepatocellular carcinoma 4, and demonstrates altered isoform usage in acute myeloid leukemia where SRPK1 inhibition produces anti-leukemic effects partly through MED24 isoform switching 5. Additionally, fine-mapping studies identified MED24 as a likely causal gene in bipolar disorder 67, suggesting roles in neurodevelopment and neurotransmission.