Anti-Astrin/SPAG5, clone 8B2 Antibody clone 8B2, from rat

Astrin/SPAG5 is a microtubule binding and cytoskeleton associated signaling protein that plays not only a critical role in mitotic spindle and chromosome segregation but also as an important signal transducer in mTOR and GSK3 beta signaling pathways. Astrin/SPAG5 is localized in the cytoplasm and/or mitotic apparatus (in dividing cells) and centrosomes. In non-dividing cells Astrin/SPAG5 is associated with microtubules unless under cellular stress, then it is localized in stress granules. Astrin/SPAG5 is expressed in many tissues but is very high in testis and sperm and is regulated via the cell cycle highest levels are seen in prophase. Recent research has focused on Astrin/SPAG5 critical role in regulating mTORC1 and its effects on growth and survival. When cells are stress Astrin/SPAG5 inhibits mTORC1 association and recruits the mTORC1 component raptor to stress granules (SGs), thereby preventing mTORC1-hyperactivation-induced apoptosis. Because cancerous tumor cells are often stressed, this mechanism is believed to be key to their survival, thus Astrin/SPAG5 activity repression is being examined as potential anti-cancer therapy.