TAF4B is a cell type-specific subunit of the general transcription factor TFIID that functions as a gene-selective coactivator 1. It plays a central role in mediating promoter responses to various activators and repressors, functioning as a transcriptional coactivator of the p65/RELA NF-κB subunit and regulating antiapoptotic genes including TNFAIP3 [UniProt]. TAF4B is particularly enriched in gonadal tissues, where it regulates critical developmental processes. In oogenesis, TAF4B occupies proximal promoters of essential meiosis regulators including Stra8, Dazl, Figla, and Nobox, being required for their proper expression and supporting prophase I progression 2. In spermatogenesis, TAF4B interacts with ZFP628 to regulate stage-specific gene expression, with TAF4B deficiency resulting in male infertility 3. The EEF1B2-TAF4B axis regulates human spermatogonial stem cell proliferation and self-renewal 4. TAF4B dysregulation is associated with cancer progression, correlating with Cyclin D2 expression in ovarian tumors and altered in 26% of high-grade serous ovarian cancers 5. TAF4B collaborates with AP-1 family members to regulate integrin alpha6 expression during epithelial-to-mesenchymal transition 6. Additionally, TAF4B is a direct target of miR-34a-5p, linking it to Huntington's disease pathomechanisms 7.