TY - JOUR
T1 - Rab1 GTPase promotes expression of β-adrenergic receptors in rat pulmonary microvascular endothelial cells
AU - Li, Yuncheng
AU - Wang, Guansong
AU - Lin, Kexiong
AU - Yin, Hongjin
AU - Zhou, Changxi
AU - Liu, Ting
AU - Wu, Guangyu
AU - Qian, Guisheng
N1 - Funding Information:
We much appreciate Dr. Guangyu Wu for the critical comments, good suggestions on this manuscript, and kindly providing the Wild type. Rab1-pcDNA3, Rab1N124I (dominant negative mutant)-pcDNA3, pDsRed2-ER, and human β 2 -AR tagged with green fluorescent protein (GFP). This work was supported by Grants 30770928 and 30971309 from National Science Foundation of China (NSFC) (to G.W.) and the PLA Grants 08G093 (to G.W.) and 06G083 (to G.Q.), and the National Institutes of Health grant R01GM076167(to G. Wu.).
PY - 2010/7
Y1 - 2010/7
N2 - It is known that Rab1 regulates the expression and function of beta-adrenoceptors (β-ARs) in many cells. However, the effect of these changes in rat pulmonary microvascular endothelial cells (RPMVECs) is not known. In the present study, we investigated the role of Rab1, a Ras-like GTPase that coordinates protein transport from the endoplasmic reticulum (ER) to the Golgi body and regulates the cell-surface targeting and function of endogenous β-ARs in RPMVECs in the presence of lipopolysaccharide (LPS). We found that lentivirus-driven expression of wild-type Rab1 (Rab1WT) in RPMVECs strongly enhanced the amount of β-ARs on the cell surface, whereas the dominant-negative mutant Rab1N124I significantly attenuated β-ARs expression on the cell surface. In addition, LPS stimulation significantly reduced β-ARs expression on the cell surface in RPMVECs; however, this effect was reversed by over-expression of wild-type Rab1WT. Fluorescent microscopy analysis demonstrated that expression of Rab1N124I and Rab1 small interfering RNA (siRNA) significantly induced the accumulation of green fluorescent protein (GFP)-tagged β2-AR in the ER. Consistent with their effects on β-ARs export, Rab1WT and Rab1N124I differentially modified the β-AR-mediated activation of extracellular signal-regulated kinase1/2 (ERK1/2). Importantly, over-expression of Rab1WT markedly reduced LPS-induced hyper-permeability of RPMVECs by increasing the expression of β2-AR on the cell surface. These data reveal that β-ARs function in RPMVECs could be modulated by manipulating β-ARs traffic from the ER to the Golgi body. We propose the ER-to-Golgi transport as a regulatory site for control of permeability of RPMVECs.
AB - It is known that Rab1 regulates the expression and function of beta-adrenoceptors (β-ARs) in many cells. However, the effect of these changes in rat pulmonary microvascular endothelial cells (RPMVECs) is not known. In the present study, we investigated the role of Rab1, a Ras-like GTPase that coordinates protein transport from the endoplasmic reticulum (ER) to the Golgi body and regulates the cell-surface targeting and function of endogenous β-ARs in RPMVECs in the presence of lipopolysaccharide (LPS). We found that lentivirus-driven expression of wild-type Rab1 (Rab1WT) in RPMVECs strongly enhanced the amount of β-ARs on the cell surface, whereas the dominant-negative mutant Rab1N124I significantly attenuated β-ARs expression on the cell surface. In addition, LPS stimulation significantly reduced β-ARs expression on the cell surface in RPMVECs; however, this effect was reversed by over-expression of wild-type Rab1WT. Fluorescent microscopy analysis demonstrated that expression of Rab1N124I and Rab1 small interfering RNA (siRNA) significantly induced the accumulation of green fluorescent protein (GFP)-tagged β2-AR in the ER. Consistent with their effects on β-ARs export, Rab1WT and Rab1N124I differentially modified the β-AR-mediated activation of extracellular signal-regulated kinase1/2 (ERK1/2). Importantly, over-expression of Rab1WT markedly reduced LPS-induced hyper-permeability of RPMVECs by increasing the expression of β2-AR on the cell surface. These data reveal that β-ARs function in RPMVECs could be modulated by manipulating β-ARs traffic from the ER to the Golgi body. We propose the ER-to-Golgi transport as a regulatory site for control of permeability of RPMVECs.
KW - Beta-adrenergic receptors
KW - Lipopolysaccharide
KW - Permeability
KW - Rab1 GTPase
KW - Small interfering RNA
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U2 - 10.1016/j.biocel.2010.04.009
DO - 10.1016/j.biocel.2010.04.009
M3 - Article
C2 - 20417717
AN - SCOPUS:77953536687
SN - 1357-2725
VL - 42
SP - 1201
EP - 1209
JO - International Journal of Biochemistry and Cell Biology
JF - International Journal of Biochemistry and Cell Biology
IS - 7
ER -