scholarly journals The Mechanism of Polyplex Internalization into Cells: Testing the GM1/Caveolin-1 Lipid Raft Mediated Endocytosis Pathway

2010 ◽  
Vol 7 (1) ◽  
pp. 267-279 ◽  
Author(s):  
Rong Qi ◽  
Douglas G. Mullen ◽  
James R. Baker ◽  
Mark M. Banaszak Holl
Keyword(s):  
Lipid Raft ◽  
Caveolin 1 ◽  
Endocytosis Pathway

scholarly journals Lipid rafts mediate internalization of β1-integrin in migrating intestinal epithelial cells

2008 ◽  
Vol 295 (5) ◽  
pp. G965-G976 ◽  
Author(s):  
Elena V. Vassilieva ◽  
Kirsten Gerner-Smidt ◽  
Andrei I. Ivanov ◽  
Asma Nusrat
Keyword(s):  
Epithelial Cells ◽  
Lipid Rafts ◽  
Lipid Raft ◽  
Intestinal Epithelial Cells ◽  
Focal Adhesions ◽  
Endocytic Pathway ◽  
Dependent Manner ◽  
Intestinal Epithelial ◽  
Caveolin 1 ◽  
Cell Matrix

Intestinal mucosal inflammation is associated with epithelial wounds that rapidly reseal by migration of intestinal epithelial cells (IECs). Cell migration involves cycles of cell-matrix adhesion/deadhesion that is mediated by dynamic turnover (assembly and disassembly) of integrin-based focal adhesions. Integrin endocytosis appears to be critical for deadhesion of motile cells. However, mechanisms of integrin internalization during remodeling of focal adhesions of migrating IECs are not understood. This study was designed to define the endocytic pathway that mediates internalization of β1-integrin in migrating model IECs. We observed that, in SK-CO15 and T84 colonic epithelial cells, β1-integrin is internalized in a dynamin-dependent manner. Pharmacological inhibition of clathrin-mediated endocytosis or macropinocytosis and small-interfering RNA (siRNA)-mediated knock down of clathrin did not prevent β1-integrin internalization. However, β1-integrin internalization was inhibited following cholesterol extraction and after overexpression of lipid raft protein, caveolin-1. Furthermore, internalized β1-integrin colocalized with the lipid rafts marker cholera toxin, and siRNA-mediated knockdown of caveolin-1 and flotillin-1/2 increased β1-integrin endocytosis. Our data suggest that, in migrating IEC, β1-integrin is internalized via a dynamin-dependent lipid raft-mediated pathway. Such endocytosis is likely to be important for disassembly of integrin-based cell-matrix adhesions and therefore in regulating IEC migration and wound closure.

scholarly journals Caveolin-1 interacts with a lipid raft-associated population of fatty acid synthase

Cell Cycle ◽  
2008 ◽  
Vol 7 (14) ◽  
pp. 2257-2267 ◽  
Author(s):  
Dolores Di Vizio ◽  
Rosalyn M. Adam ◽  
Jayoung Kim ◽  
Robert Kim ◽  
Federica Sotgia ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Lipid Raft ◽  
Fatty Acid Synthase ◽  
Caveolin 1

scholarly journals Erratum: HPV-16 E5 oncoprotein upregulates lipid raft components caveolin-1 and ganglioside GM1 at the plasma membrane of cervical cells

Oncogene ◽  
2008 ◽  
Vol 27 (49) ◽  
pp. 6396-6396 ◽  
Author(s):  
F A Suprynowicz ◽  
G L Disbrow ◽  
E Krawczyk ◽  
V Simic ◽  
K Lantzky ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Lipid Raft ◽  
Ganglioside Gm1 ◽  
Hpv 16 ◽  
Caveolin 1 ◽  
E5 Oncoprotein ◽  
Cervical Cells

Abstract 706: HDL and ApoA-I Inhibit Palmitate-induced Lipid Raft Trafficking of TLR4 and Inflammatory Cytokines Expression in Adipocytes

2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Hodaka Yamada ◽  
Tomio Umemoto ◽  
Taeko Ohtani ◽  
Harue Fukaya ◽  
Mikihiko Kawano ◽  
...  
Keyword(s):  
Gene Expression ◽  
Immune System ◽  
Inflammatory Cytokines ◽  
Lipid Raft ◽  
Disease Risk ◽  
Saturated Fatty Acids ◽  
Cardiovascular Disease Risk ◽  
Caveolin 1 ◽  
Discontinuous Sucrose Gradient ◽  
Inflammatory Molecules

Background: Adipose tissue inflammation induces inflammatory molecules production leading to insulin resistance and increased cardiovascular disease risk. Recently it has become apparent that innate immune system is activated by saturated fatty acids (SFAs) by a process involved in TLR4 signaling. HDL and apoA-I has anti-inflammatory effects, however the mechanisms are not well understood in adipocytes. Aims: We examined to elucidate the effect of HDL and/or ApoA-I mediated cholesterol efflux on induction of inflammatory gene expression by palmitate in adipocytes via TLR4 dependent immune system. Methods: 3T3-L1 adipocytes are exposure to 250uM palmitate for periods of up to 24 hours with or without HDL or Apo A-I. Antisense directed to ABCG-1 or ABCA-1 is added 24 hours prior to each reagent challenge. Cells were harvested and estimated for expression of Saa 3 gene using real-time PCR or detection of TLR4 in raft or non raft by western blotting. Lipid rafts were purified by ultracentrifugation on discontinuous sucrose gradient, and identified by the presence of caveolin-1. Results: TLR4 was translocated into lipid raft from non raft within 15 minutes and dislocated by 60 minutes after palmitate exposure. Saa 3 gene expression was significantly up-regulated by 24 hours palmitate exposure in adipocytes. TLR4 translocation to raft and Saa 3 gene up- regulation induced by palmitate was significantly inhibited by pretreatment of HDL or Apo A-I for 6 hours. Antisense directed to ABCG-1 or SRB1 abrogated these inhibitory effects by HDL, but not ApoA-I whereas antisense to ABCA-1 did by Apo A-I but not HDL. Conclusions: These findings suggest that TLR4 mediates palmitate-induced Saa 3 gene expression in adipocytes. A reduction in membrane cholesterol mediated by ABCG-1, SRB1 or ABCA-1 can account for the ability of HDL or ApoA-I to disrupt stimulation of inflammatory cytokines by palmitate

scholarly journals HPV-16 E5 oncoprotein upregulates lipid raft components caveolin-1 and ganglioside GM1 at the plasma membrane of cervical cells

Oncogene ◽  
2007 ◽  
Vol 27 (8) ◽  
pp. 1071-1078 ◽  
Author(s):  
F A Suprynowicz ◽  
G L Disbrow ◽  
E Krawczyk ◽  
V Simic ◽  
K Lantzky ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Lipid Raft ◽  
Ganglioside Gm1 ◽  
Hpv 16 ◽  
Caveolin 1 ◽  
E5 Oncoprotein ◽  
Cervical Cells

CAVEOLIN-1 INTERACTS WITH A LIPID RAFT-ASSOCIATED POPULATION OF FATTY ACID SYNTHASE IN PROSTATE CANCER

2008 ◽  
Vol 179 (4S) ◽  
pp. 456-457
Author(s):  
Dolores Di Vizio ◽  
Rosalyn M Adam ◽  
Jayoung Kim ◽  
Keith R Solomon ◽  
Robert Kim ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Fatty Acid ◽  
Lipid Raft ◽  
Fatty Acid Synthase ◽  
Caveolin 1

Connexin Family Members Target to Lipid Raft Domains and Interact with Caveolin-1†

Biochemistry ◽  
2002 ◽  
Vol 41 (18) ◽  
pp. 5754-5764 ◽  
Author(s):  
Anne-Lane Schubert ◽  
William Schubert ◽  
David C. Spray ◽  
Michael P. Lisanti
Keyword(s):  
Lipid Raft ◽  
Family Members ◽  
Caveolin 1 ◽  
Raft Domains

scholarly journals Respiratory syncytial virus assembly occurs in GM1-rich regions of the host-cell membrane and alters the cellular distribution of tyrosine phosphorylated caveolin-1

2002 ◽  
Vol 83 (8) ◽  
pp. 1841-1850 ◽  
Author(s):  
Gaie Brown ◽  
Helen W. McL. Rixon ◽  
Richard J. Sugrue
Keyword(s):  
Respiratory Syncytial Virus ◽  
Cell Surface ◽  
Host Cell ◽  
Lipid Raft ◽  
Cellular Distribution ◽  
Assembly Process ◽  
Caveolin 1 ◽  
Cytoplasmic Vesicles ◽  
Infected Cells ◽  
Syncytial Virus

We have previously shown that respiratory syncytial virus (RSV) assembly occurs within regions of the host-cell surface membrane that are enriched in the protein caveolin-1 (cav-1). In this report, we have employed immunofluorescence microscopy to further examine the RSV assembly process. Our results show that RSV matures at regions of the cell surface that, in addition to cav-1, are enriched in the lipid-raft ganglioside GM1. Furthermore, a comparison of mock-infected and RSV-infected cells by confocal microscopy revealed a significant change in the cellular distribution of phosphocaveolin-1 (pcav-1). In mock-infected cells, pcav-1 was located at regions of the cell that interact with the extracellular matrix, termed focal adhesions (FA). In contrast, RSV-infected cells showed both a decrease in the levels of pcav-1 associated with FA and the appearance of pcav-1-containing cytoplasmic vesicles, the latter being absent in mock-infected cells. These cytoplasmic vesicles were clearly visible between 9 and 18 h post-infection and coincided with the formation of RSV filaments, although we did not observe a direct association of pcav-1 with mature virus. In addition, we noted a strong colocalization between pcav-1 and growth hormone receptor binding protein-7 (Grb7), within these cytoplasmic vesicles, which was not observed in mock-infected cells. Collectively, these findings show that the RSV assembly process occurs within specialized lipid-raft structures on the host-cell plasma membrane, induces the cellular redistribution of pcav-1 and results in the formation of cytoplasmic vesicles that contain both pcav-1 and Grb7.

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