BLZF1 (basic leucine zipper nuclear factor 1) is a ubiquitously expressed 45-kDa nuclear protein encoded by a 3-kb mRNA that plays critical roles in intracellular protein trafficking and transcriptional regulation 1. Functionally, BLZF1 is required for maintaining normal Golgi apparatus structure and mediating protein transport from the endoplasmic reticulum through the Golgi to the cell surface. The protein exhibits dual localization patterns: a full-length form accumulates in the nucleus while an alternatively spliced 23-kDa isoform localizes cytoplasmically 1. BLZF1 functions as a transcriptional regulator interacting directly with DNMT3L and other transcription factors to direct site-specific DNA methylation 2, and serves as a substrate for tankyrase-dependent PARsylation and RNF146-mediated degradation in Wnt/β-catenin signaling regulation 3. In disease contexts, BLZF1 has documented relevance to tumorigenesis: it acts as a Golgi-localizing partner for mutant KIT in gastrointestinal stromal tumors, facilitating aberrant signaling and drug resistance 4. Reduced BLZF1 expression in hepatocellular carcinoma correlates with poor prognosis and increased recurrence risk 5. Additionally, BLZF1 variants associate with venous thromboembolism susceptibility 6, suggesting broader cardiovascular relevance.