TY - JOUR
T1 - Ral GTPases Regulate Exocyst Assembly through Dual Subunit Interactions
AU - Moskalenko, Serge
AU - Tong, Chao
AU - Rosse, Carine
AU - Mirey, Gladys
AU - Formstecher, Etienne
AU - Daviet, Laurent
AU - Camonis, Jacques
AU - White, Michael A.
PY - 2003/12/19
Y1 - 2003/12/19
N2 - Ral GTPases have been implicated in the regulation of a variety of dynamic cellular processes including proliferation, oncogenic transformation, actin-cytoskeletal dynamics, endocytosis, and exocytosis. Recently the Sec6/8 complex, or exocyst, a multisubunit complex facilitating post-Golgi targeting of distinct subclasses of secretory vesicles, has been identified as a bona fide Ral effector complex. Ral GTPases regulate exocyst-dependent vesicle trafficking and are required for exocyst complex assembly. Sec5, a membrane-associated exocyst subunit, has been identified as a direct target of activated Ral; however, the mechanism by which Ral can modulate exocyst assembly is unknown. Here we report that an additional component of the exocyst, Exo84, is a direct target of activated Ral. We provide evidence that mammalian exocyst components are present as distinct subcomplexes on vesicles and the plasma membrane and that Ral GTPases regulate the assembly interface of a full octameric exocyst complex through interaction with Sec5 and Exo84.
AB - Ral GTPases have been implicated in the regulation of a variety of dynamic cellular processes including proliferation, oncogenic transformation, actin-cytoskeletal dynamics, endocytosis, and exocytosis. Recently the Sec6/8 complex, or exocyst, a multisubunit complex facilitating post-Golgi targeting of distinct subclasses of secretory vesicles, has been identified as a bona fide Ral effector complex. Ral GTPases regulate exocyst-dependent vesicle trafficking and are required for exocyst complex assembly. Sec5, a membrane-associated exocyst subunit, has been identified as a direct target of activated Ral; however, the mechanism by which Ral can modulate exocyst assembly is unknown. Here we report that an additional component of the exocyst, Exo84, is a direct target of activated Ral. We provide evidence that mammalian exocyst components are present as distinct subcomplexes on vesicles and the plasma membrane and that Ral GTPases regulate the assembly interface of a full octameric exocyst complex through interaction with Sec5 and Exo84.
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U2 - 10.1074/jbc.M308702200
DO - 10.1074/jbc.M308702200
M3 - Article
C2 - 14525976
AN - SCOPUS:0346154744
SN - 0021-9258
VL - 278
SP - 51743
EP - 51748
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 51
ER -