Exerts an anti-apoptotic effect in the immune system and is involved in responses to infections. Abundantly expressed in the thymus (in thymocytes), spleen (in splenocytes), lymph node, followed by bone marrow and lung. Belongs to the TRAFAC class TrmE-Era-EngA-EngB-Septin-like GTPase superfamily. AIG1/Toc34/Toc159-like paraseptin GTPase family. IAN subfamily.