SSNA1 (Sjögren's syndrome nuclear autoantigen 1) is a microtubule-binding protein that plays critical roles in cytoskeletal organization and cell division. SSNA1 functions as a potent microtubule-stabilizing protein that modulates dynamic instability by slowing growth, shrinkage, and catastrophe rates while promoting rescue events 1. The protein forms anti-parallel coiled-coil structures with self-assembly facilitated by C-terminal residues that create triple-stranded helical junctions, which serve as microtubule-binding hubs 2. SSNA1 localizes to centrosomes and centrioles, where it is essential for proper cell division and cytokinesis 3. The protein also acts as a sensor of microtubule damage, becoming enriched at damage sites and protecting microtubules from severing by spastin 1. In neuronal development, SSNA1 promotes axon outgrowth and branching 3. Clinically, SSNA1 has emerged as a potential biomarker in cancer, with elevated expression associated with hepatocellular carcinoma metastasis through STAT3/EMT pathway regulation 4 and serving as an autoantigen target in gastric cancer with prognostic significance 5. SSNA1 deletion significantly reduces embryonic viability and causes multipolar spindles during cell division 2.