Van Deurs Research Articles

Expression of mutant dynamin inhibits toxicity and transport of endocytosed ricin to the Golgi apparatus.

Endocytosis and intracellular transport of ricin were studied in stable transfected HeLa cells where overexpression of wild-type (WT) or mutant dynamin is regulated by tetracycline. Overexpression of the temperature-sensitive mutant dynG273D at the nonpermissive temperature or the dynK44A mutant inhibits clathrin-dependent endocytosis (Damke, H., T. Baba, A.M. van der Blieck, and S.L. Schmid. 1995. J. Cell Biol. 131: 69-80; Damke, H., T. Baba, D.E. Warnock, and S.L. Schmid. 1994. J. Cell Biol. 127:915-934). Under these conditions, ricin was endocytosed at a normal level. Surprisingly, overexpression of both mutants made the cells less sensitive to ricin. Butyric acid and trichostatin A treatment enhanced dynamin overexpression and increased the difference in toxin sensitivity between cells with normal and mutant dynamin. Intoxication with ricin seems to require toxin transport to the Golgi apparatus (Sandirg, K., and B. van Deurs. 1996. Physiol. Rev. 76:949-966), and this process was monitored by measuring the incorporation of radioactive sulfate into a modified ricin molecule containing a tyrosine sulfation site. The sulfation of ricin was much greater in cells expressing dynWT than in cells expressing dynK44A. Ultrastructural analysis using a ricin-HRP conjugate confirmed that transport to the Golgi apparatus was severely inhibited in cells expressing dynK44A. In contrast, ricin transport to lysosomes as measured by degradation of 125I-ricin was essentially unchanged in cells expressing dynK44A. These data demonstrate that although ricin is internalized by clathrin-independent endocytosis in cells expressing mutant dynamin, there is a strong and apparently selective inhibition of ricin transport to the Golgi apparatus. Also, in cells with mutant dynamin, there is a redistribution of the mannose-6-phosphate receptor.

The GDP/GTP cycle of Rab5 in the regulation of endocytotic membrane traffic.

In eukaryotic cells, endocytosis plays a central role in the maintenance of cellular organization and function. The endocytotic route is composed of separate stations that carry out specialized functions such as uptake of nutrients, clearance of metabolites from the medium, internalization and down-regulation of receptors, turnover of membranes, and antigen processing. Proteins, lipids, and solutes internalized at the cell surface are first transported into early endosomes. The best-characterized route to this compartment is the clathrin-coated-vesicles-mediated route (Robinson 1994), but non-clathrin-mediated mechanisms also contribute to the endocytotic traffic (Watts and Marsh 1992; Sandvig and van Deurs 1994). From the early endosomes, internalized constituents can be either recycled to the cell surface, possibly through a recycling compartment distinct from the early endosome (Yamashiro and Maxfield 1984; Dunn et al. 1989; Hopkins et al. 1994), or transported to late endosomes and lysosomes for degradation. The endocytotic pathway is also connected to the exocytotic...

Molecules internalized by clathrin-independent endocytosis are delivered to endosomes containing transferrin receptors.

We have previously demonstrated that the preendosomal compartment in addition to clathrin-coated vesicles, comprises distinct nonclathrin coated endocytic vesicles mediating clathrin-independent endocytosis (Hansen, S. H., K. Sandvig, and B. van Deurs. 1991. J. Cell Biol. 113:731-741). Using K+ depletion in HEp-2 cells to block clathrin-dependent but not clathrin-independent endocytosis, we have now traced the intracellular routing of these nonclathrin coated vesicles to see whether molecules internalized by clathrin-independent endocytosis are delivered to a unique compartment or whether they reach the same early and late endosomes as encountered by molecules internalized with high efficiency through clathrin-coated pits and vesicles. We find that Con A-gold internalized by clathrin-independent endocytosis is delivered to endosomes containing transferrin receptors. After incubation of K(+)-depleted cells with Con A-gold for 15 min, approximately 75% of Con A-gold in endosomes is colocalized with transferrin receptors. Endosomes containing only Con A-gold may be accounted for either by depletion of existing endosomes for transferrin receptors or by de novo generation of endosomes. Cationized gold and BSA-gold internalized in K(+)-depleted cells are also delivered to endosomes containing transferrin receptors. h-lamp-1-enriched compartments are only reached occasionally within 30 min in K(+)-depleted as well as in control cells. Thus, preendosomal vesicles generated by clathrin-independent endocytosis do not fuse to any marked degree with late endocytic compartments. These data show that in HEp-2 cells, molecules endocytosed without clathrin are delivered to the same endosomes as reached by transferrin receptors internalized through clathrin-coated pits.

Protein toxins: mode of action and cell entry.

Conference Article| November 01 1992 Protein toxins: mode of action and cell entry Kirsten Sandvig; Kirsten Sandvig 1Institute for Cancer Research at The Norwegian Radium Hospital, Montebello, 0310 Oslo 3, Norway Search for other works by this author on: This Site PubMed Google Scholar Elena Dubinina; Elena Dubinina *WA Engelhardt Institute for Molecular Biology, Academy of Sciences of Russia, Vavilov str 32, Moscow, Russia Search for other works by this author on: This Site PubMed Google Scholar Garred Øystein; Garred Øystein 1Institute for Cancer Research at The Norwegian Radium Hospital, Montebello, 0310 Oslo 3, Norway Search for other works by this author on: This Site PubMed Google Scholar Kristian Prydz; Kristian Prydz 1Institute for Cancer Research at The Norwegian Radium Hospital, Montebello, 0310 Oslo 3, Norway Search for other works by this author on: This Site PubMed Google Scholar Juri V. Kozlov; Juri V. Kozlov *WA Engelhardt Institute for Molecular Biology, Academy of Sciences of Russia, Vavilov str 32, Moscow, Russia Search for other works by this author on: This Site PubMed Google Scholar Steen H. Hansen; Steen H. Hansen †Structural Cell Biology Unit, Department of Anatomy, The Panum Institute, University of Copenhagen, DK-2200 Copenhagen N, Denmark Search for other works by this author on: This Site PubMed Google Scholar Bo van Deurs Bo van Deurs †Structural Cell Biology Unit, Department of Anatomy, The Panum Institute, University of Copenhagen, DK-2200 Copenhagen N, Denmark Search for other works by this author on: This Site PubMed Google Scholar Biochem Soc Trans (1992) 20 (4): 724–727. https://doi.org/10.1042/bst0200724 Article history Received: July 10 1992 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Cite Icon Cite Get Permissions Citation Kirsten Sandvig, Elena Dubinina, Garred Øystein, Kristian Prydz, Juri V. Kozlov, Steen H. Hansen, Bo van Deurs; Protein toxins: mode of action and cell entry. Biochem Soc Trans 1 November 1992; 20 (4): 724–727. doi: https://doi.org/10.1042/bst0200724 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsBiochemical Society Transactions Search Advanced Search Keywords: HRP, horseradish peroxidase, TGN, trans-Golgi network This content is only available as a PDF. © 1992 Biochemical Society1992 Article PDF first page preview Close Modal You do not currently have access to this content.

Endocytosis: what goes in and how?

ABSTRACT During the last decade the term ‘endocytosis’ has become virtually synonymous with the activity of clathrin-coated vesicles. These vesicles, which are derived from cell surface clathrin-coated pits, are transport vehicles responsible for the transfer of plasma membrane receptors and their ligands, between the first two stations of the endocytic pathway: namely, the plasma membrane and early endosomes (Goldstein et al., 1985; van Deurs et al., 1989; Griffiths and Gruenberg, 1991). Despite the irrefutable evidence that clathrin-coated vesicles mediate endocytosis, their contribution to the total endocytic activity of the cell and the composition of the membrane they internalise remains controversial. Here we discuss: (1) the evidence that non-clathrin-mediated endocytic mechanisms operate alongside the clathrin-mediated pathway; (2) the evidence that endocytosis occurs for surface molecules that are not enriched in clathrin-coated pits and; (3) the sorting activities of cell surface clathrincoated pits and the notion that plasma membrane proteins that show particularly slow rates of uptake are actively excluded from the endocytic pathway.

Characterization of the cytochalasin D-resistant (pinocytic) mechanisms of endocytosis utilized by chlamydiae

The cytochalasin D-resistant (pinocytic) portion of the entry of two chlamydia strains (Chlamydia trachomatis L2/434/Bu and Chlamydia psittaci GPIC [guinea pig inclusion conjunctivitis]) was examined. By ultrastructural criteria, few organisms of either strain were observed in association with coated host-cell plasma membrane during entry into McCoy cells; this argues against a coated-pit mechanism of entry. When association with a coated membrane was seen, coat material appeared to pinch off ahead of internalizing chlamydiae. However, entry of both strains was substantially reduced by cytosol acidification, a procedure shown to prevent coated-pit vesiculation (K. Sandvig, S. Olsnes, O. W. Petersen, and B. van Deurs, J. Cell Biol. 105:679-689, 1987). No conclusive evidence of displacement of the fluid-phase marker [3H]sucrose from constitutively forming endocytic vesicles was found. Indeed the entry of strain 434 (but not strain GPIC) was accompanied by the influx of a large volume of fluid, suggesting an inducible mechanism. Additionally, entry of strain 434 (but not strain GPIC) was partially inhibitable by amiloride, yet the drug had no effect on the entry of transferrin, a ligand known to enter solely via coated pits. Our findings endorse the view that chlamydial entry can occur via a pathway involving coated pits. However, the unusual morphology of entry and lack of fluid exclusion are consistent with a process whereby although chlamydiae are not fully enclosed by coat material, their entry is dependent on the vesiculation of coated pits. Furthermore, the data support the proposition that a significant proportion of the entry of strain 434 occurs via an inducible pathway independent of coated-pit uptake.

Correlation between protein data in normal lumbar CSF and morphological findings of choroid plexus epithelium: a biochemical corroboration of barrier transport via tight junction pores

Specific "reference areas" were derived from relationships between the proteins prealbumin, albumin, alpha 1-acid glycoprotein, alpha 2-macroglobulin, total transferrin, IgG, IgA, IgM, and the corresponding total protein in normal lumbar CSF samples. The procedure for calculating the boundary lines of these reference areas was carried out on the basis of double standard deviations in subgroups with total protein differences of 50 ml/l within the whole range of 150-400 ml/l CSF. The resulting biochemical data, hydrodynamic radii of the individual proteins investigated, and van Deurs' and Koehler's morphological findings on the existence of pores in the barrier-forming tight junctions of the choroid plexus epithelium could be surprisingly well correlated with one another, although these morphological findings were obtained in choroid plexus of the rat brain. The correlation allowed the conclusion that proteins undergo ultrafiltration via a pattern of tight junction pores with various diameters. However, the molecular mechanism seems to include an additional facilitating component.

Receptor-mediated endocytosis of ricin: B. van Deurs, L. Pedersen, S. Olsnes, K. Sandvig, and A. Sundan, Department of Anatomy, The Panum Institute, Copenhagen, Denmark and Norsk Hydro's Institute for Cancer Research and the Norwegian Cancer Society, Montebello, Oslo, Norway

Receptor-mediated endocytosis of ricin: B. van Deurs, L. Pedersen, S. Olsnes, K. Sandvig, and A. Sundan, Department of Anatomy, The Panum Institute, Copenhagen, Denmark and Norsk Hydro's Institute for Cancer Research and the Norwegian Cancer Society, Montebello, Oslo, Norway

Heterogeneity and endocytosis in the established human breast cancer cell line MCF-7 demonstrated with a monoclonal antibody: O. W. Petersen, P. Briand, J. Hilkens, J. Hilgers, and B. van Deurs, Department of Anatomy, The Panum Institute, Copenhagen, Denmark; The Fibiger Laboratory, Copenhagen, Denmark; and Department of Genetics, The Netherlands Cancer Institute, Amsterdam, The Netherlands

Heterogeneity and endocytosis in the established human breast cancer cell line MCF-7 demonstrated with a monoclonal antibody: O. W. Petersen, P. Briand, J. Hilkens, J. Hilgers, and B. van Deurs, Department of Anatomy, The Panum Institute, Copenhagen, Denmark; The Fibiger Laboratory, Copenhagen, Denmark; and Department of Genetics, The Netherlands Cancer Institute, Amsterdam, The Netherlands

Filipin as a cholesterol probe: Olav Behnke, Jørgen Tranum-Jensen, and Bo van Deurs, Anatomy Departments A and C, The Panum Institute, University of Copenhagen, DK-2200 Copenhagen N, Denmark

Filipin as a cholesterol probe: Olav Behnke, Jørgen Tranum-Jensen, and Bo van Deurs, Anatomy Departments A and C, The Panum Institute, University of Copenhagen, DK-2200 Copenhagen N, Denmark

House fly resistance to chemicals.

It is no doubt significant that housefly resistance to DDT was first recognized and reported in Europe, where DDT came into commercial use in 1944 and was used extensively by civil and military personnel in 1945. In 1947, Sacca and Missiroli attributed the failure of DDT to control flies in Italy to the presence of a variety of house fly which had become resistant to DDT. About the same time Wiesmann (1947) reported house fly resistance in Sweden. Two years later Keiding and Van Deurs (1949) in three short paragraphs summarized the course of events which was apparently common throughout Europe, as follows: “Already in 1946 there were some isolated complaints of failing effect, and in the summer of 1947 the fly control failed in a great many places.