Matches in SemOpenAlex for { <https://semopenalex.org/work/W2049202619> ?p ?o ?g. }
Showing items 1 to 64 of
64
with 100 items per page.
- W2049202619 endingPage "1148" @default.
- W2049202619 startingPage "1147" @default.
- W2049202619 abstract "Have you seen?30 March 2015free access Plasmolipin—a new player in endocytosis and epithelial development Armelle Le Guelte Armelle Le Guelte Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA Search for more papers by this author Ian G Macara Ian G Macara [email protected] Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA Search for more papers by this author Armelle Le Guelte Armelle Le Guelte Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA Search for more papers by this author Ian G Macara Ian G Macara [email protected] Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA Search for more papers by this author Author Information Armelle Le Guelte1 and Ian G Macara1 1Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA The EMBO Journal (2015)34:1147-1148https://doi.org/10.15252/embj.201591448 See also: AE Rodríguez-Fraticelli et al (March 2015) PDFDownload PDF of article text and main figures. ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InMendeleyWechatReddit Figures & Info Polarized vesicle sorting is essential not only for epithelial cell function but also for cell polarization and tissue morphogenesis. Endocytosis is a key determinant of the surface abundance of plasma membrane proteins and is highly regulated. In an important recent paper, Rodríguez-Fraticelli et al (2015) identify a new player in apical endocytosis—a previously uncharacterized protein called Plasmolipin. They report not only its mechanism of action through binding to an epsin, but also highlight an essential role in regulating Notch signaling, which controls epithelial differentiation. Despite decades of work by multiple laboratories on the mechanisms of endocytosis, the full complement of proteins involved in this process likely remains incomplete. This is particularly the case for polarized epithelia, which possess multiple endocytic pathways. In addition, most studies on vesicle traffic in higher organisms have been performed on cell lines grown in 2D cultures, which probably lack some of the components needed by functional tissues in vivo. To address this issue, Rodriguez-Faticelli and colleagues recently screened for genes expressed in the zebrafish midgut that were induced during lumen formation and expansion (Rodríguez-Fraticelli et al, 2015). They identified a gene called plasmolipin (pllp), which encodes a tetraspanin protein of unknown function. Plasmolipin (PLLP) contains a MARVEL domain that is associated with proteins involved in vesicle traffic (Sanchez-Pulido et al, 2002), and is highly expressed in the brain where it is associated with myelin, but is also found in the apical region of epithelial cells. The authors exploited the power of zebrafish genetics to create transgenic animals either defective in pllp or that express a PLLP-GFP fusion protein. They found expression of pllp in the posterior midgut and specifically in the apical region of the intestinal epithelial cells. PLLP-GFP localized to vesicles, apical microvilli, and basal endosomes. Zebrafish mutant for pllp, created using TALEN gene editing, showed defects in intestinal absorption, and the intestinal epithelial cells contained enlarged endosomes. Moreover, PLLP partially co-localized with Rab11—a marker of the apical recycling endosome (ARE) compartment—and in the absence of PLLP, Rab11 was mislocalized. Taken together, these data strongly suggested an essential function for PLLP in apical endocytosis. The authors confirmed this hypothesis using MDCK cells and found that the over-expression of PLLP is sufficient to enhance the formation of the ARE. Their next goal was to determine the molecular mechanism underlying this function. The authors used the powerful BioID method (Roux et al, 2012) to biotinylate and isolate proteins that might interact with PLLP. Of 42 candidates, 20 were associated with vesicle sorting. Two major interactors were an epsin, EpsR, which is required for retrograde transport from late endosomes, and Syntaxin 7 (Stx7), which is a known cargo for EpsR and drives fusion with endosomal membrane (Miller et al, 2007). Silencing of either EpsR or Stx7 phenocopied loss of PLLP in MDCK cells, strongly suggesting that the interaction with these proteins is of functional importance. What are the consequences of disrupting apical endocytosis through PLLP? In addition to absorption of nutrients by the intestine, and ion transport in the kidney, the morphogenesis of epithelial tissues itself is dependent on the traffic of apical vesicles. The abundance of the polarity protein Crumbs (Crb) at the apical cortex, for example, controls the size of the apical domain, and defects in either delivery or endocytosis would likely alter its abundance with deleterious consequences to epithelial function. Indeed, the pllp-mutant zebrafish exhibits abnormal apical accumulation of Crb3 in the intestinal epithelium, and a similar phenotype was found in MDCK cells, together with a defect in the enrichment of Crb3 at the tight junctions. The authors used an elegant methodology called RUSH, developed by Franck Perez and colleagues, to address the dynamics of Crb3 delivery, in which a biotin-tagged protein is trapped in the endoplasmic reticulum through association with an ER-resident streptavidin (Boncompain et al, 2012). Addition of biotin to the cells releases the tagged protein, so its subsequent transport through the vesicular system of the cell can be tracked. In this case, the Crb3 could be observed to arrive first at the apical surface, and later became enriched at the tight junctions. This enrichment was lost in the absence of PLLP. Inversely, the over-expression of PLLP resulted in decreased apical Crb3. As a second example of the importance of PLLP-dependent apical transport, the authors examined Notch signaling, which is required for the differentiation of intestinal epithelia (Fre et al, 2011) and which in Drosophila is known to involve Stx7 (Vaccari et al, 2008). Importantly, the mutant pllp zebrafish showed reduced Notch signaling and defects in intestinal epithelial differentiation, a phenotype that could be recapitulated by a zebrafish mutant in the Notch pathway or by chemical inhibition of Notch signaling. Ligand engagement of Notch induces the proteolytic cleavage of Notch to release an intracellular domain (NICD), and NICD levels were significantly reduced by silencing of PLLP or EpsR, which suppressed Notch1 endocytosis. Notch ligands are also membrane associated. When MDCK cells expressing Notch1 were co-cultured above cells that express the ligands Delta-1 or Jagged-1, the silencing of PLLP expression specifically blocked activation of Notch signaling by Jagged-1 (Fig 1). This is perhaps surprising since it is the basal surface rather than the apical surface of the MDCK cells that would presumably make contact with the ligand-expressing cells. The authors also co-cultured MDCK cells expressing Jagged-1 with the Notch1 MDCK cells and found again that PLLP or EpsR knockdown suppressed signaling—even though it would be the lateral membranes that would contact one another in this situation rather than the apical membranes. These data suggest that PLLP function is not confined to the apical domain, but is also needed for basolateral endocytosis. Figure 1. PLLP is required for Notch signaling and zebrafish midgut differentiationPLLP regulates Notch signaling through endocytosis and results in correct patterning of the posterior midgut. In the absence of PLLP, Notch signaling is impaired and induces defects in intestinal epithelial cell differentiation, model based on Rodríguez-Fraticelli et al (2015). Download figure Download PowerPoint Together, this interesting study identifies a novel function for the uncharacterized PLLP protein in the promotion of epithelial endocytosis, and reveals the importance of this function in fine-tuning Notch signaling, which is essential for the proper development and differentiation of the intestinal epithelium, particularly of the posterior gut absorptive cells. It will be of great interest to explore PLLP function in other tissues where it is expressed at high levels, such as the brain and kidney, and to determine if it is coupled to Notch signaling in these other situations. It will also be important to determine if PLLP is regulated solely by expression level or is subject to post-translational modifications, whether its function is restricted to specific cargoes, and to explore further the mechanism through which it promotes endocytosis. References Boncompain G, Divoux S, Gareil N, de Forges H, Lescure A, Latreche L, Mercanti V, Jollivet F, Raposo G, Perez F (2012) Synchronization of secretory protein traffic in populations of cells. Nat Methods 9: 493–498CrossrefCASPubMedWeb of Science®Google Scholar Fre S, Bardin A, Robine S, Louvard D (2011) Notch signaling in intestinal homeostasis across species: the cases of Drosophila, Zebrafish and the mouse. Exp Cell Res 317: 2740–2747CrossrefCASPubMedWeb of Science®Google Scholar Miller SE, Collins BM, McCoy AJ, Robinson MS, Owen DJ (2007) A SNARE-adaptor interaction is a new mode of cargo recognition in clathrin-coated vesicles. Nature 450: 570–574CrossrefCASPubMedWeb of Science®Google Scholar Rodríguez-Fraticelli AE, Bagwell J, Bosch-Fortea M, Boncompain G, Reglero-Real N, Garcia-Leon MJ, Andrés G, Toribio ML, Alonso MA, Millán J, Perez F, Bagnat M, Martín-Belmonte F (2015) Developmental regulation of apical endocytosis controls epithelial patterning in vertebrate tubular organs. Nat Cell Biol 17: 241–250CrossrefCASPubMedWeb of Science®Google Scholar Roux KJ, Kim DI, Raida M, Burke B (2012) A promiscuous biotin ligase fusion protein identifies proximal and interacting proteins in mammalian cells. J Cell Biol 196: 801–810CrossrefCASPubMedWeb of Science®Google Scholar Sanchez-Pulido L, Martin-Belmonte F, Valencia A, Alonso MA (2002) MARVEL: a conserved domain involved in membrane apposition events. Trends Biochem Sci 27: 599–601CrossrefCASPubMedWeb of Science®Google Scholar Vaccari T, Lu H, Kanwar R, Fortini ME, Bilder D (2008) Endosomal entry regulates Notch receptor activation in Drosophila melanogaster. J Cell Biol 180: 755–762CrossrefCASPubMedWeb of Science®Google Scholar Previous ArticleNext Article Read MoreAbout the coverClose modalView large imageVolume 34,Issue 9,5 May 2015Cover: Grasping for air – This photograph of a green sea turtle emerging from the water was taken by Ljiljana Milenkovic, a developmental biologist at the Stanford University School of Medicine. Volume 34Issue 95 May 2015In this issue FiguresReferencesRelatedDetailsLoading ..." @default.
- W2049202619 created "2016-06-24" @default.
- W2049202619 creator A5002460941 @default.
- W2049202619 creator A5061812426 @default.
- W2049202619 date "2015-03-30" @default.
- W2049202619 modified "2023-09-28" @default.
- W2049202619 title "Plasmolipin—a new player in endocytosis and epithelial development" @default.
- W2049202619 cites W2010378383 @default.
- W2049202619 cites W2041642727 @default.
- W2049202619 cites W2070594316 @default.
- W2049202619 cites W2077919099 @default.
- W2049202619 cites W2078461181 @default.
- W2049202619 cites W2105707485 @default.
- W2049202619 cites W2118642448 @default.
- W2049202619 doi "https://doi.org/10.15252/embj.201591448" @default.
- W2049202619 hasPubMedCentralId "https://www.ncbi.nlm.nih.gov/pmc/articles/4426476" @default.
- W2049202619 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/25825384" @default.
- W2049202619 hasPublicationYear "2015" @default.
- W2049202619 type Work @default.
- W2049202619 sameAs 2049202619 @default.
- W2049202619 citedByCount "3" @default.
- W2049202619 countsByYear W20492026192020 @default.
- W2049202619 countsByYear W20492026192021 @default.
- W2049202619 countsByYear W20492026192022 @default.
- W2049202619 crossrefType "journal-article" @default.
- W2049202619 hasAuthorship W2049202619A5002460941 @default.
- W2049202619 hasAuthorship W2049202619A5061812426 @default.
- W2049202619 hasBestOaLocation W20492026192 @default.
- W2049202619 hasConcept C170493617 @default.
- W2049202619 hasConcept C28005876 @default.
- W2049202619 hasConcept C54355233 @default.
- W2049202619 hasConcept C70721500 @default.
- W2049202619 hasConcept C86803240 @default.
- W2049202619 hasConcept C95444343 @default.
- W2049202619 hasConceptScore W2049202619C170493617 @default.
- W2049202619 hasConceptScore W2049202619C28005876 @default.
- W2049202619 hasConceptScore W2049202619C54355233 @default.
- W2049202619 hasConceptScore W2049202619C70721500 @default.
- W2049202619 hasConceptScore W2049202619C86803240 @default.
- W2049202619 hasConceptScore W2049202619C95444343 @default.
- W2049202619 hasIssue "9" @default.
- W2049202619 hasLocation W20492026191 @default.
- W2049202619 hasLocation W20492026192 @default.
- W2049202619 hasLocation W20492026193 @default.
- W2049202619 hasLocation W20492026194 @default.
- W2049202619 hasOpenAccess W2049202619 @default.
- W2049202619 hasPrimaryLocation W20492026191 @default.
- W2049202619 hasRelatedWork W1873165927 @default.
- W2049202619 hasRelatedWork W1978427724 @default.
- W2049202619 hasRelatedWork W2009527912 @default.
- W2049202619 hasRelatedWork W2016622933 @default.
- W2049202619 hasRelatedWork W2023037801 @default.
- W2049202619 hasRelatedWork W2091304198 @default.
- W2049202619 hasRelatedWork W2888760763 @default.
- W2049202619 hasRelatedWork W2903155987 @default.
- W2049202619 hasRelatedWork W3027798089 @default.
- W2049202619 hasRelatedWork W4226150306 @default.
- W2049202619 hasVolume "34" @default.
- W2049202619 isParatext "false" @default.
- W2049202619 isRetracted "false" @default.
- W2049202619 magId "2049202619" @default.
- W2049202619 workType "article" @default.