STYXL1 (serine/threonine/tyrosine interacting like 1) is a catalytically inactive pseudophosphatase with diverse cellular functions. In reproductive biology, STYXL1 serves as a germ cell-specific cofactor for the CCT complex, facilitating tubulin folding essential for sperm flagella development and male fertility 1. The protein regulates cellular trafficking and lysosomal function by modulating endoplasmic reticulum stress responses, with STYXL1 depletion enhancing β-glucocerebrosidase trafficking to lysosomes 2. In cancer biology, STYXL1 demonstrates oncogenic properties in glioma, promoting cell growth, migration, and invasion 3, and in hepatocellular carcinoma by downregulating CELF2 through the PI3K/Akt pathway 4. The gene shows clinical significance as a potential biomarker, being differentially expressed in late-onset major depressive disorder 5 and diabetes 6. Additionally, genetic variants near STYXL1 are associated with sarcoidosis susceptibility 7. These findings establish STYXL1 as a multifunctional pseudophosphatase with roles in reproduction, cellular stress responses, cancer progression, and various disease states.