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  • Exocyst
  • The Exocyst is a conserved hetero-octameric protein complex, which regulates different aspects of protein trafficking, including tethering of the Golgi-derived vesicles to target membranes. (uiowa.edu)
  • Although Ral GTPases have been proposed to mediate assembly of Exocyst holocomplexes, we hypothesize that they actually serve to allosterically regulate Exocyst functions by promoting association or disassociation of additional factors. (uiowa.edu)
  • Here we investigate roles of Ral GTPases and the Exocyst in regulating basolateral protein trafficking using Madin Darby canine kidney (MDCK) cells and RNA interference (RNAi) technology. (uiowa.edu)
  • One of our research interests is the evolutionarily conserved multi-protein complex, named the exocyst. (upenn.edu)
  • The exocyst is specifically localized to sites of active exocytosis and polarized cell growth, and is a downstream effector of many small GTPases including Rab, Rho, and Ral. (upenn.edu)
  • Under the control of these signaling proteins, the exocyst coordinates with cytoskeletons in processes such as cytokinesis, ciliogeneisis, and cell migration. (upenn.edu)
  • M-Sec promotes membrane nanotube formation by interacting with Ral and the exocyst complex. (nih.gov)
  • Furthermore, blockage of the interaction of M-Sec with Ral and the exocyst complex, which serves as a downstream effector of Ral, attenuated the formation of membrane nanotubes. (nih.gov)
  • Our results reveal that M-Sec functions as a key regulator of membrane nanotube formation through interaction with the Ral-exocyst pathway. (nih.gov)
  • Furthermore, we show that Rab11 forms a complex with Sec5 and that Sec5 interacts with Sec6 suggesting that the exocyst is a Rab11 effector that facilitates protein transport to the apical rhabdomere in Drosophila PRCs. (pubmedcentralcanada.ca)
  • exocytosis
  • We also show that a Ral-uncoupled Sec5 mutant, but not a Ral-uncoupled Exo84 mutant, inhibits E-cadherin exocytosis. (uiowa.edu)
  • Our study may provide new insights into mechanisms regulating protein trafficking in epithelial cells, and potentially lead to development of new therapeutic targets for the treatment of diseases in which exocytosis is impaired, such as Polycystic kidney disease and diabetes. (uiowa.edu)
  • Ral-mediated exocytosis is also involved such biological processes as platelet activation, immune cell functions, neuronal plasticity, and regulation of insulin action. (wikipedia.org)
  • Exocytosis is a basic cell biological process mediated by transport, docking, and fusion of secretory vesicles carrying proteins and lipids to the plasma membrane. (upenn.edu)
  • Also through exocytosis, membrane proteins and lipids can be incorporated into specific domains of plasma membrane for cell surface expansion, cell growth, morphogenesis, and cell migration. (upenn.edu)
  • Instead the protein, which is predominantly expressed at high levels in mammalian postmitotic central nervous system neurons, functions in diverse processes such as synaptic plasticity and neuronal migration through phosphorylation of proteins required for cytoskeletal organization, endocytosis and exocytosis, and apoptosis. (cancerindex.org)
  • viral oncogene
  • Receptor and non-receptor tyrosine kinases, such as Met and Src (v-Src Avian Sacroma (Schmidt-Ruppin A-2) Viral Oncogene), respectively, along with other PTKs (Protein Tyrosine Kinases) have an active function in this process, as they phosphorylate tyrosine residues in the short intra-cytoplasmic tail of E-Cadherins, thereby promoting their internalization by endocytosis. (sabiosciences.com)
  • Regulation
  • Due to its exocytotic role in platelets, immune cells, neurons, and insulin regulation, downregulation of Ral may lead to pathological conditions such as thrombosis and metabolic syndrome. (wikipedia.org)
  • The proteomic analysis revealed the presence of 21 proteins known to be associated with specific renal diseases or blood pressure regulation. (pnas.org)
  • Unlike other members of the family, the protein encoded by this gene does not directly control cell cycle regulation. (cancerindex.org)
  • The level of junction proteins at the site of cell-cell contacts is modulated by transcriptional regulation and/or protein degradation through the Ubiquitin-Proteasome pathway. (sabiosciences.com)
  • Apart from transcriptional regulation endocytosis and recycling of junction proteins is an alternative mechanism allowing cells to undergo rapid changes in morphology in response to extracellular stimuli (Ref.3). (sabiosciences.com)
  • For monomeric G-proteins, the effect may be a rapid (2 min) and bimodal up-regulation, a transiently unimodal activation, or a transient down-regulation. (plantphysiol.org)
  • S. R. Sprang, Z. Chen, and X. Du, "Structural basis of effector regulation and signal termination in heterotrimeric G α proteins," Advances in Protein Chemistry , vol. 74, pp. 1-65, 2007. (hindawi.com)
  • plasma membrane
  • Immunoblotting of urinary membrane fractions has revealed that, in addition to AQP2, the kidneys excrete membranes containing apical plasma-membrane transporter proteins from each renal tubule segment ( 5 ), suggesting that analysis of urinary membrane fractions could provide noninvasive information about the pathophysiological state of the entire renal tubule. (pnas.org)
  • We hypothesize that AQP2 and other apical plasma-membrane proteins are excreted through the process of exosome formation, i.e., delivery of the internal vesicles of multivesicular bodies (MVBs) to the urinary space by fusion of the outer membrane of MVBs with the apical plasma membrane of renal tubule epithelial cells. (pnas.org)
  • Here we use immunoelectron microscopy and nanospray liquid chromatography-tandem MS (LC-MS/MS) analysis of urinary membrane proteins to show that AQP2 and other apical plasma-membrane proteins are excreted through the process of exosome formation in agreement with the predictions above. (pnas.org)
  • During differentiation, epithelial cells polarize, leading to the formation of two distinct plasma membrane domains, the apical and basolateral domains. (physiology.org)
  • Establishment and maintenance of ion channels within a specific plasma membrane domain play an important role in determining the physiological function of an epithelial cell. (physiology.org)
  • Most signal transduction involves the binding of extracellular signaling molecules (or ligands ) to cell-surface receptors that face outward from the plasma membrane and trigger events inside the cell. (chemeurope.com)
  • Plasma membrane domains of polarized cells display distinct protein and lipid compositions. (pubmedcentralcanada.ca)
  • apical
  • However, it remains a mystery how aquaporin-2 (an integral membrane protein) and other apical transporters are delivered to the urine. (pnas.org)
  • cytoskeletal
  • Tyrosine Kinases also phosphorylate Ctnn-Beta and p120Ctn causing disassociation of cytoskeletal proteins from junctions and thereby weakening junction morphology (Ref.4). (sabiosciences.com)
  • receptor
  • Ral and phospholipase D2-dependent pathway for constitutive metabotropic glutamate receptor endocytosis. (uwo.ca)
  • A G protein-coupled receptor at work: the rhodopsin model," Trends in Biochemical Sciences , vol. 34, no. 11, pp. 540-552, 2009. (hindawi.com)
  • A. V. Smrcka, "G protein βγ subunits: central mediators of G protein-coupled receptor signaling," Cellular and Molecular Life Sciences , vol. 65, no. 14, pp. 2191-2214, 2008. (hindawi.com)
  • B. Konig and M. Gratzel, "Site of dopamine D 1 receptor binding to G s protein mapped with synthetic peptides," Biochimica et Biophysica Acta , vol. 1223, no. 2, pp. 261-266, 1994. (hindawi.com)
  • signal transduction
  • ion channels are essential for a variety of the physiological processes performed by epithelial cells, including extracellular ion and volume homeostasis and signal transduction. (physiology.org)
  • The number of proteins and other molecules participating in the events involving signal transduction increases as the process emanates from the initial stimulus, resulting in a "signal cascade," beginning with a relatively small stimulus that elicits a large response. (chemeurope.com)
  • Other candidates that have emerged as possible components of the ethylene signal transduction pathway are monomeric GTP-binding proteins (monomeric G-proteins). (plantphysiol.org)
  • extracellular
  • The Adherens Junctions have a crucial role both as sensors of extracellular stimuli and in regulating the dynamics of epithelial cell sheets or with neighboring cells. (sabiosciences.com)
  • The extracellular domain of E-Cadherin binds to Ca2+ (Calcium) and forms complexes with the extracellular domains of E-Cadherin molecules on neighboring cells. (sabiosciences.com)
  • receptors
  • Many, but not all, steroids have receptors within the cytoplasm, and usually act by stimulating the binding of their receptors to the promoter region of steroid-responsive genes. (chemeurope.com)
  • A. O. Shpakov, "The molecular determinants in the serpentine type receptors, responsible for its functional coupling with the heterotrimeric G-protein," Tsitologiia , vol. 44, pp. 242-258, 2002 (Russian). (hindawi.com)
  • pathway
  • Proteomic analysis of urinary vesicles through nanospray liquid chromatography-tandem mass spectrometry identified numerous protein components of MVBs and of the endosomal pathway in general. (pnas.org)
  • tyrosine
  • It binds to tyrosine phosphorylated E-Cadherins and facilitates the internalization and subsequent Ubiquitin-dependent degradation of E-Cadherins. (sabiosciences.com)
  • induces
  • Integrin signaling also induces formation of a complex of p130Cas, the adapter protein Crk, and a third molecule, DOCK 180, that is required for membrane ruffling, a component of cell migration ( 13 , 14 ). (jimmunol.org)
  • vesicles
  • Third, the urinary vesicles should contain proteins typical of MVBs and of exosomes formed by other cell types ( 7 ). (pnas.org)
  • Although the core principles of how membrane bound vesicles exchange material between the organelles of a cell have been known for some time ( Pfeffer, 2013 ), there remains much interest in the mechanism by which this process is regulated. (frontiersin.org)
  • cell migration
  • IQGAP1 captures and stabilizes Microtubules/Tubulins through the Mt-BPs (Microtubule-Plus-End-Binding Proteins), APC (Adenomatous Polyposis Coli) and CLIP170 (Cytoplasmic Linker Protein-170Alpha-2), leading to establishment of polarized cell morphology and directional cell migration. (sabiosciences.com)
  • Despite the similarities, the functions of Rap1 and Rap2 have not been completely elucidated although recent studies suggest that both Rap proteins may be involved in cell migration and adhesion. (ubc.ca)
  • cells
  • This G-LISA™ Rho activation assay measures the levels of GTP-loaded RhoA in cells. (cytoskeleton.com)
  • The identification of cancer marker regulatory components that act not alone, but within networks, represents an invaluable resource for elucidating the moxlecular mechanisms that govern the uncontrolled proliferation of cancer cells, as well as for catalyzing the development of protein panels with biomarker and drug target potential, screening tests with improved sensitivity and specificity, and novel cancer therapies aimed at pursuing multiple drug targets. (biomedcentral.com)
  • Together these enzymes and proteins constitute a PA signaling toolkit that mediates the signaling functions of PA in cells. (frontiersin.org)
  • The GP precursor is post-translationally cleaved by the pro-protein convertase furin within the Golgi compartment of virus-producer cells, yielding two disulfide-linked subunits, GP1 and GP2 [ 13 ]. (mdpi.com)
  • amino acid
  • Such conserved motifs include the Src homology 3 (SH3) domain that binds to proline-rich amino acid sequences (Pro-X-X-Pro) ( 62 , 82 ) and the PDZ domain, a 80- to 90-amino acid modular protein interaction domain, named after the three proteins in which this domain was first identified (PSD-95/Discs large protein/ZO-1) ( 45 , 96 ). (physiology.org)
  • family
  • p120Ctn (p120Catenin), another member of the Catenin family, binds to the juxtamembrane region of E-Cadherin and stabilizes Cadherin molecules at the cell surface. (sabiosciences.com)