Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 7 of 7
Full-Text Articles in Medical Cell Biology
Pv1 Down-Regulation Via Shrna Inhibits The Growth Of Pancreatic Adenocarcinoma Xenografts, Sophie J. Deharvengt, Dan Tse, Olga Sideleva, Caitlin Mcgarry, Jason R. Gunn, Daniel S. Longnecker, Catherine Carriere, Radu V. Stan
Pv1 Down-Regulation Via Shrna Inhibits The Growth Of Pancreatic Adenocarcinoma Xenografts, Sophie J. Deharvengt, Dan Tse, Olga Sideleva, Caitlin Mcgarry, Jason R. Gunn, Daniel S. Longnecker, Catherine Carriere, Radu V. Stan
Dartmouth Scholarship
PV1 is an endothelial-specific protein with structural roles in the formation of diaphragms in endothelial cells of normal vessels. PV1 is also highly expressed on endothelial cells of many solid tumours. On the basis of in vitro data, PV1 is thought to actively participate in angiogenesis. To test whether or not PV1 has a function in tumour angiogenesis and in tumour growth in vivo, we have treated pancreatic tumour-bearing mice by single-dose intratumoural delivery of lentiviruses encoding for two different shRNAs targeting murine PV1. We find that PV1 down-regulation by shRNAs inhibits the growth of established tumours derived from two …
Caveolae, Fenestrae And Transendothelial Channels Retain Pv1 On The Surface Of Endothelial Cells, Eugene Tkachenko, Dan Tse, Olga Sideleva, Sophie J. Deharvengt, Marcus R. Luciano, Yan Xu, Caitlin L. Mcgarry, John Chidlow, Paul F. Pilch, William C. Sessa, Derek K. Toomre, Radu V. Stan
Caveolae, Fenestrae And Transendothelial Channels Retain Pv1 On The Surface Of Endothelial Cells, Eugene Tkachenko, Dan Tse, Olga Sideleva, Sophie J. Deharvengt, Marcus R. Luciano, Yan Xu, Caitlin L. Mcgarry, John Chidlow, Paul F. Pilch, William C. Sessa, Derek K. Toomre, Radu V. Stan
Dartmouth Scholarship
PV1 protein is an essential component of stomatal and fenestral diaphragms, which are formed at the plasma membrane of endothelial cells (ECs), on structures such as caveolae, fenestrae and transendothelial channels. Knockout of PV1 in mice results in in utero and perinatal mortality. To be able to interpret the complex PV1 knockout phenotype, it is critical to determine whether the formation of diaphragms is the only cellular role of PV1. We addressed this question by measuring the effect of complete and partial removal of structures capable of forming diaphragms on PV1 protein level. Removal of caveolae in mice by knocking …
Seg1 Controls Eisosome Assembly And Shape, Karen E. Moreira, Sebastian Schuck, Bianca Schrul, Florian Fröhlich, James B. Moseley
Seg1 Controls Eisosome Assembly And Shape, Karen E. Moreira, Sebastian Schuck, Bianca Schrul, Florian Fröhlich, James B. Moseley
Dartmouth Scholarship
Eisosomes are stable domains at the plasma membrane of the budding yeast Saccharomyces cerevisiae and have been proposed to function in endocytosis. Eisosomes are composed of two main cytoplasmic proteins, Pil1 and Lsp1, that form a scaffold around furrow-like plasma membrane invaginations. We show here that the poorly characterized eisosome protein Seg1/Ymr086w is important for eisosome biogenesis and architecture. Seg1 was required for efficient incorporation of Pil1 into eisosomes and the generation of normal plasma membrane furrows. Seg1 preceded Pil1 during eisosome formation and established a platform for the assembly of other eisosome components. This platform was further shaped and …
Transport Of Ldl-Derived Cholesterol From The Npc1 Compartment To The Er Involves The Trans-Golgi Network And The Snare Protein Complex, Yasuomi Urano, Hiroshi Watanabe, Stephanie R. Murphy, Yohei Shibuya, Yong Geng, Andrew Peden, Catherine Chang, Ta Yuan Chang
Transport Of Ldl-Derived Cholesterol From The Npc1 Compartment To The Er Involves The Trans-Golgi Network And The Snare Protein Complex, Yasuomi Urano, Hiroshi Watanabe, Stephanie R. Murphy, Yohei Shibuya, Yong Geng, Andrew Peden, Catherine Chang, Ta Yuan Chang
Dartmouth Scholarship
Mammalian cells acquire cholesterol mainly from LDL. LDL enter the endosomes, allowing cholesteryl esters to be hydrolyzed by acid lipase. The hydrolyzed cholesterol (LDL-CHOL) enters the Niemann-Pick type C1 (NPC1)-containing endosomal compartment en route to various destinations. Whether the Golgi is involved in LDL-CHOL transport downstream of the NPC1 compartment has not been demonstrated. Using subcellular fractionation and immunoadsorption to enrich for specific membrane fractions, here we show that, when parental Chinese hamster ovary (CHO) cells are briefly exposed to (3)H-cholesteryl linoleate (CL) labeled-LDL, newly liberated (3)H-LDL-CHOL appears in membranes rich in trans-Golgi network (TGN) long before it becomes available …
Interdependent Assembly Of Specific Regulatory Lipids And Membrane Fusion Proteins Into The Vertex Ring Domain Of Docked Vacuoles, Rutilio A. Fratti, Youngsoo Jun, Alexey J. Merz, Nathan Margolis, William Wickner
Interdependent Assembly Of Specific Regulatory Lipids And Membrane Fusion Proteins Into The Vertex Ring Domain Of Docked Vacuoles, Rutilio A. Fratti, Youngsoo Jun, Alexey J. Merz, Nathan Margolis, William Wickner
Dartmouth Scholarship
Membrane microdomains are assembled by lipid partitioning (e.g., rafts) or by protein-protein interactions (e.g., coated vesicles). During docking, yeast vacuoles assemble "vertex" ring-shaped microdomains around the periphery of their apposed membranes. Vertices are selectively enriched in the Rab GTPase Ypt7p, the homotypic fusion and vacuole protein sorting complex (HOPS)-VpsC Rab effector complex, SNAREs, and actin. Membrane fusion initiates at vertex microdomains. We now find that the "regulatory lipids" ergosterol, diacylglycerol and 3- and 4-phosphoinositides accumulate at vertices in a mutually interdependent manner. Regulatory lipids are also required for the vertex enrichment of SNAREs, Ypt7p, and HOPS. Conversely, SNAREs and actin …
Trans-Snare Interactions Elicit Ca2+ Efflux From The Yeast Vacuole Lumen, Alexey J. Merz, William T. Wickner
Trans-Snare Interactions Elicit Ca2+ Efflux From The Yeast Vacuole Lumen, Alexey J. Merz, William T. Wickner
Dartmouth Scholarship
Ca2+ transients trigger many SNARE-dependent membrane fusion events. The homotypic fusion of yeast vacuoles occurs after a release of lumenal Ca2+. Here, we show that trans-SNARE interactions promote the release of Ca2+ from the vacuole lumen. Ypt7p-GTP, the Sec1p/Munc18-protein Vps33p, and Rho GTPases, all of which function during docking, are required for Ca2+ release. Inhibitors of SNARE function prevent Ca2+ release. Recombinant Vam7p, a soluble Q-SNARE, stimulates Ca2+ release. Vacuoles lacking either of two complementary SNAREs, Vam3p or Nyv1p, fail to release Ca2+ upon tethering. Mixing these two vacuole populations together allows Vam3p and Nyv1p to interact in trans and …
Three V-Snares And Two T-Snares, Present In A Pentameric Cis-Snare Complex On Isolated Vacuoles, Are Essential For Homotypic Fusion, Christian Ungermann, Gabriele F. Von Mollard, Ole N. Jensen, Nathan Margolis, Tom H. Stevens, William Wickner
Three V-Snares And Two T-Snares, Present In A Pentameric Cis-Snare Complex On Isolated Vacuoles, Are Essential For Homotypic Fusion, Christian Ungermann, Gabriele F. Von Mollard, Ole N. Jensen, Nathan Margolis, Tom H. Stevens, William Wickner
Dartmouth Scholarship
Vacuole SNAREs, including the t-SNAREs Vam3p and Vam7p and the v-SNARE Nyv1p, are found in a multisubunit "cis" complex on isolated organelles. We now identify the v-SNAREs Vti1p and Ykt6p by mass spectrometry as additional components of the immunoisolated vacuolar SNARE complex. Immunodepletion of detergent extracts with anti-Vti1p removes all the Ykt6p that is in a complex with Vam3p, immunodepletion with anti-Ykt6p removes all the Vti1p that is complexed with Vam3p, and immunodepletion with anti-Nyv1p removes all the Ykt6p in complex with other SNAREs, demonstrating that they are all together in the same cis multi-SNARE complex. After priming, which disassembles …