The ARTS connection: role of ARTS in apoptosis and cancer.

ARTS is an unusual septin that is localized to mitochondria in living cells and promotes apoptosis by antagonizing IAPs. ARTS functions as a tumor suppressor in Acute Lymphoblastic Leukemia (ALL) and is lost in more than 70% of leukemic patients. The loss of ARTS is specific as levels of H5, a closely related non-apoptotic septin protein derived from the same gene, were unaffected. Thus, ARTS, a new member in the mitochondrial pro-apoptotic arsenal, provides a link between mitochondria, apoptosis and cancer.