DYNLT1 (dynein light chain Tctex-type 1) is a component of the cytoplasmic dynein motor complex that functions in intracellular transport along microtubules 1. The protein is involved in viral protein trafficking, particularly for D-type retrovirus gag polyproteins targeting cytoplasmic assembly sites, and plays roles in microtubule-based movement, mitotic spindle assembly, and ciliary function. Mechanistically, DYNLT1 participates in protein folding regulation during spermatogenesis, where it functions with chaperone HSPA8 to enable proper head-tail coupling apparatus assembly in sperm 2. In cancer cells, DYNLT1 colocalizes with voltage-dependent anion channel 1 (VDAC1) on mitochondria, where it stabilizes VDAC1 by inhibiting Parkin-mediated ubiquitination, thereby promoting mitochondrial metabolism and ATP production 1. Clinically, DYNLT1 dysregulation associates with multiple diseases. In male infertility, DYNLT1 mRNA expression is significantly decreased in spermatozoa from infertile patients across various etiologies, including varicocele and idiopathic infertility 3, 4. Conversely, DYNLT1 is upregulated in breast tumors, particularly ER+ and triple-negative subtypes, promoting cancer cell proliferation and migration 1. DYNLT1 expression is also downregulated in whole blood of Huntington's disease patients, with changes correlating to disease progression 5. Additionally, DYNLT1 emerges as a candidate diagnostic biomarker for metabolic dysfunction-associated steatohepatitis and sepsis 6, 7.