Rab37 is a novel mast cell specific GTPase localized to secretory granules

GTPases regulate a myriad of cellular functions including signal transducti on, cytoskeletal organization and membrane trafficking. Rab GTPases act to coordinate the membrane dynamics of cells by organizing and regulating the activity of effector proteins important in vesicle trafficking. Rab37 is a novel Rab GTPase specifically expressed in the MC-9 mast cell line and bone marrow mast cells, Rab37 is 74% identical to Rab26 and 47% identical to Ra bs, a GTPase important in Golgi to plasma membrane vesicle trafficking in m ammalian cells, When green fluorescent protein tagged Rab37 is expressed in bone marrow mast cells, the secretory granules are labeled. These data sug gest that Rab37 may play an important role in mast cell degranulation makin g this protein a potentially important target for therapeutic intervention in the treatment of allergy. (C) 2000 Federation of European Biochemical So cieties.