RT Journal Article
T1 Rab18 dynamics in adipocytes in relation to lipogenesis, lipolysis and obesity.
A1 Pulido, Marina R
A1 Díaz-Ruiz, Alberto
A1 Jiménez-Gómez, Yolanda
A1 García-Navarro, Socorro
A1 Gracia-Navarro, Francisco
A1 Tinahones, Francisco
A1 López-Miranda, José
A1 Frühbeck, Gema
A1 Vázquez-Martínez, Rafael
A1 Malagón, María M
K1 Rab18 protein, mouse
K1 Adipocitos
K1 Adiponectina
K1 Western Blotting
K1 Células Cultivadas
K1 Retículo Endoplásmico
K1 Hipoglucemiantes
K1 Técnicas para Inmunoenzimas
K1 Metabolismo de los Lípidos
K1 Obesidad
K1 Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
K1 Células 3T3-L1
K1 Insulina
AB Lipid droplets (LDs) are organelles that coordinate lipid storage and mobilization, both processes being especially important in cells specialized in managing fat, the adipocytes. Proteomic analyses of LDs have consistently identified the small GTPase Rab18 as a component of the LD coat. However, the specific contribution of Rab18 to adipocyte function remains to be elucidated. Herein, we have analyzed Rab18 expression, intracellular localization and function in relation to the metabolic status of adipocytes. We show that Rab18 production increases during adipogenic differentiation of 3T3-L1 cells. In addition, our data show that insulin induces, via phosphatidylinositol 3-kinase (PI3K), the recruitment of Rab18 to the surface of LDs. Furthermore, Rab18 overexpression increased basal lipogenesis and Rab18 silencing impaired the lipogenic response to insulin, thereby suggesting that this GTPase promotes fat accumulation in adipocytes. On the other hand, studies of the β-adrenergic receptor agonist isoproterenol confirmed and extended previous evidence for the participation of Rab18 in lipolysis. Together, our data support the view that Rab18 is a common mediator of lipolysis and lipogenesis and suggests that the endoplasmic reticulum (ER) is the link that enables Rab18 action on these two processes. Finally, we describe, for the first time, the presence of Rab18 in human adipose tissue, wherein the expression of this GTPase exhibits sex- and depot-specific differences and is correlated to obesity. Taken together, these findings indicate that Rab18 is involved in insulin-mediated lipogenesis, as well as in β-adrenergic-induced lipolysis, likely facilitating interaction of LDs with ER membranes and the exchange of lipids between these compartments. A role for Rab18 in the regulation of adipocyte biology under both normal and pathological conditions is proposed.
PB Public Library of Science
YR 2011
FD 2011-07-28
LK http://hdl.handle.net/10668/1157
UL http://hdl.handle.net/10668/1157
LA en
NO Pulido MR, Diaz-Ruiz A, Jiménez-Gómez Y, Garcia-Navarro S, Gracia-Navarro F, Tinahones F, et al. Rab18 dynamics in adipocytes in relation to lipogenesis, lipolysis and obesity. PLoS ONE. 2011; 6(7):e22931
NO Journal Article; Research Support, Non-U.S. Gov't;
DS RISalud
RD Apr 19, 2025