Heike Fölsch | Northwestern University Feinberg School of Medicine (original) (raw)
Papers by Heike Fölsch
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Sep 14, 2017
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Oct 23, 2007
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Nov 18, 2002
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Apr 19, 2011
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Apr 3, 2006
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Feb 5, 2007
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Nov 18, 2008
Newly synthesized basolateral markers can traverse recycling endosomes en route to the surface of... more Newly synthesized basolateral markers can traverse recycling endosomes en route to the surface of Madin-Darby canine kidney cells; however, the routes used by apical proteins are less clear. Here, we functionally inactivated subsets of endocytic compartments and examined the effect on surface delivery of the basolateral marker vesicular stomatitis virus glycoprotein (VSV-G), the raft-associated apical marker influenza hemagglutinin (HA), and the non-raft-associated protein endolyn. Inactivation of transferrin-positive endosomes after internalization of horseradish peroxidase (HRP)-containing conjugates inhibited VSV-G delivery, but did not disrupt apical delivery. In contrast, inhibition of protein export from apical recycling endosomes upon expression of dominant-negative constructs of myosin Vb or Sec15 selectively perturbed apical delivery of endolyn. Ablation of apical endocytic components accessible to HRP-conjugated wheat germ agglutinin (WGA) disrupted delivery of HA but not endolyn. However, delivery of glycosylphosphatidylinositolanchored endolyn was inhibited by 450% under these conditions, suggesting that the biosynthetic itinerary of a protein is dependent on its targeting mechanism. Our studies demonstrate that apical and basolateral proteins traverse distinct endocytic intermediates en route to the cell surface, and that multiple routes exist for delivery of newly synthesized apical proteins.
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Mar 13, 2013
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Apr 5, 2007
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Aug 13, 2003
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Apr 10, 2005
F1000 - Post-publication peer review of the biomedical literature, 2015
F1000 - Post-publication peer review of the biomedical literature, 2013
F1000 - Post-publication peer review of the biomedical literature, 2007
F1000 - Post-publication peer review of the biomedical literature, 2012
F1000 - Post-publication peer review of the biomedical literature, 2003
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, May 6, 2010
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Oct 29, 2003
east Ypt1p-interacting protein (Yip1p) belongs to a conserved family of transmembrane proteins th... more east Ypt1p-interacting protein (Yip1p) belongs to a conserved family of transmembrane proteins that interact with Rab GTPases. We encountered Yip1p as a constituent of ER-derived transport vesicles, leading us to hypothesize a direct role for this protein in transport through the early secretory pathway. Using a cell-free assay that recapitulates protein transport from the ER to the Golgi complex, we find that affinity-purified antibodies directed against the hydrophilic amino terminus of Yip1p potently inhibit transport. Surprisingly, inhibition is specific to the COPII-dependent budding stage. In support of this in vitro Y observation, strains bearing the temperature-sensitive yip1-4 allele accumulate ER membranes at a nonpermissive temperature, with no apparent accumulation of vesicle intermediates. Genetic interaction analyses of the yip1-4 mutation corroborate a function in ER budding. Finally, ordering experiments show that preincubation of ER membranes with COPII proteins decreases sensitivity to anti-Yip1p antibodies, indicating an early requirement for Yip1p in vesicle formation. We propose that Yip1p has a previously unappreciated role in COPII vesicle biogenesis.
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Jul 28, 2004
fndosome-to-Golgi retrieval of the mannose 6-phosphate receptor (MPR) is required for lysosome bi... more fndosome-to-Golgi retrieval of the mannose 6-phosphate receptor (MPR) is required for lysosome biogenesis. Currently, this pathway is poorly understood. Analyses in yeast identified a complex of proteins called "retromer" that is essential for endosome-to-Golgi retrieval of the carboxypeptidase Y receptor Vps10p. Retromer comprises five distinct proteins: Vps35p, 29p, 26p, 17p, and 5p, which are conserved in mammals. Here, we show that retromer is required for the efficient retrieval of the cationindependent MPR (CI-MPR). Cells lacking mammalian E VPS26 fail to retrieve the CI-MPR, resulting in either rapid degradation of or mislocalization to the plasma membrane. We have localized mVPS26 to multivesicular body endosomes by electron microscopy, and through the use of CD8 reporter protein constructs have examined the effect of loss of mVPS26 upon the trafficking of membrane proteins that cycle between the endosome and the Golgi. The data presented here support the hypothesis that retromer performs a selective function in endosome-to-Golgi transport, mediating retrieval of the CI-MPR, but not furin.
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Jan 15, 2003
Cargo transfer from trans-Golgi network (TGN)derived transport carriers to endosomes involves a s... more Cargo transfer from trans-Golgi network (TGN)derived transport carriers to endosomes involves a still unde®ned set of tethering/fusion events. Here we analyze a molecular interaction that may play a role in this process. We demonstrate that the GGAs, a family of Arf-dependent clathrin adaptors involved in selection of TGN cargo, interact with the Rabaptin-5±Rabex-5 complex, a Rab4/Rab5 effector regulating endosome fusion. These interactions are bipartite: GGA-GAE domains recognize an FGPLV sequence (residues 439±443) in a predicted random coil of Rabaptin-5 (a sequence also recognized by the g1and g2-adaptin ears), while GGA-GAT domains bind to the C-terminal coiled-coils of Rabaptin-5. The GGA±Rabaptin-5 interaction decreases binding of clathrin to the GGA-hinge domain, and expression of green¯uorescent protein (GFP)±Rabaptin-5 shifts the localization of endogenous GGA1 and associated cargo to enlarged early endosomes. These observations thus identify a binding sequence for GAE/gadaptin ear domains and reveal a functional link between proteins regulating TGN cargo export and endosomal tethering/fusion events.
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Sep 14, 2017
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Oct 23, 2007
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Nov 18, 2002
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Apr 19, 2011
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Apr 3, 2006
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Feb 5, 2007
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Nov 18, 2008
Newly synthesized basolateral markers can traverse recycling endosomes en route to the surface of... more Newly synthesized basolateral markers can traverse recycling endosomes en route to the surface of Madin-Darby canine kidney cells; however, the routes used by apical proteins are less clear. Here, we functionally inactivated subsets of endocytic compartments and examined the effect on surface delivery of the basolateral marker vesicular stomatitis virus glycoprotein (VSV-G), the raft-associated apical marker influenza hemagglutinin (HA), and the non-raft-associated protein endolyn. Inactivation of transferrin-positive endosomes after internalization of horseradish peroxidase (HRP)-containing conjugates inhibited VSV-G delivery, but did not disrupt apical delivery. In contrast, inhibition of protein export from apical recycling endosomes upon expression of dominant-negative constructs of myosin Vb or Sec15 selectively perturbed apical delivery of endolyn. Ablation of apical endocytic components accessible to HRP-conjugated wheat germ agglutinin (WGA) disrupted delivery of HA but not endolyn. However, delivery of glycosylphosphatidylinositolanchored endolyn was inhibited by 450% under these conditions, suggesting that the biosynthetic itinerary of a protein is dependent on its targeting mechanism. Our studies demonstrate that apical and basolateral proteins traverse distinct endocytic intermediates en route to the cell surface, and that multiple routes exist for delivery of newly synthesized apical proteins.
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Mar 13, 2013
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Apr 5, 2007
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Aug 13, 2003
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Apr 10, 2005
F1000 - Post-publication peer review of the biomedical literature, 2015
F1000 - Post-publication peer review of the biomedical literature, 2013
F1000 - Post-publication peer review of the biomedical literature, 2007
F1000 - Post-publication peer review of the biomedical literature, 2012
F1000 - Post-publication peer review of the biomedical literature, 2003
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, May 6, 2010
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Oct 29, 2003
east Ypt1p-interacting protein (Yip1p) belongs to a conserved family of transmembrane proteins th... more east Ypt1p-interacting protein (Yip1p) belongs to a conserved family of transmembrane proteins that interact with Rab GTPases. We encountered Yip1p as a constituent of ER-derived transport vesicles, leading us to hypothesize a direct role for this protein in transport through the early secretory pathway. Using a cell-free assay that recapitulates protein transport from the ER to the Golgi complex, we find that affinity-purified antibodies directed against the hydrophilic amino terminus of Yip1p potently inhibit transport. Surprisingly, inhibition is specific to the COPII-dependent budding stage. In support of this in vitro Y observation, strains bearing the temperature-sensitive yip1-4 allele accumulate ER membranes at a nonpermissive temperature, with no apparent accumulation of vesicle intermediates. Genetic interaction analyses of the yip1-4 mutation corroborate a function in ER budding. Finally, ordering experiments show that preincubation of ER membranes with COPII proteins decreases sensitivity to anti-Yip1p antibodies, indicating an early requirement for Yip1p in vesicle formation. We propose that Yip1p has a previously unappreciated role in COPII vesicle biogenesis.
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Jul 28, 2004
fndosome-to-Golgi retrieval of the mannose 6-phosphate receptor (MPR) is required for lysosome bi... more fndosome-to-Golgi retrieval of the mannose 6-phosphate receptor (MPR) is required for lysosome biogenesis. Currently, this pathway is poorly understood. Analyses in yeast identified a complex of proteins called "retromer" that is essential for endosome-to-Golgi retrieval of the carboxypeptidase Y receptor Vps10p. Retromer comprises five distinct proteins: Vps35p, 29p, 26p, 17p, and 5p, which are conserved in mammals. Here, we show that retromer is required for the efficient retrieval of the cationindependent MPR (CI-MPR). Cells lacking mammalian E VPS26 fail to retrieve the CI-MPR, resulting in either rapid degradation of or mislocalization to the plasma membrane. We have localized mVPS26 to multivesicular body endosomes by electron microscopy, and through the use of CD8 reporter protein constructs have examined the effect of loss of mVPS26 upon the trafficking of membrane proteins that cycle between the endosome and the Golgi. The data presented here support the hypothesis that retromer performs a selective function in endosome-to-Golgi transport, mediating retrieval of the CI-MPR, but not furin.
Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature, Jan 15, 2003
Cargo transfer from trans-Golgi network (TGN)derived transport carriers to endosomes involves a s... more Cargo transfer from trans-Golgi network (TGN)derived transport carriers to endosomes involves a still unde®ned set of tethering/fusion events. Here we analyze a molecular interaction that may play a role in this process. We demonstrate that the GGAs, a family of Arf-dependent clathrin adaptors involved in selection of TGN cargo, interact with the Rabaptin-5±Rabex-5 complex, a Rab4/Rab5 effector regulating endosome fusion. These interactions are bipartite: GGA-GAE domains recognize an FGPLV sequence (residues 439±443) in a predicted random coil of Rabaptin-5 (a sequence also recognized by the g1and g2-adaptin ears), while GGA-GAT domains bind to the C-terminal coiled-coils of Rabaptin-5. The GGA±Rabaptin-5 interaction decreases binding of clathrin to the GGA-hinge domain, and expression of green¯uorescent protein (GFP)±Rabaptin-5 shifts the localization of endogenous GGA1 and associated cargo to enlarged early endosomes. These observations thus identify a binding sequence for GAE/gadaptin ear domains and reveal a functional link between proteins regulating TGN cargo export and endosomal tethering/fusion events.