391 results on '"Fransen, J.A.M."'
Search Results
2. Fluorescence CLEM in biology: historic developments and current super-resolution applications
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Dries, K. van den, Fransen, J.A.M., Cambi, A., Dries, K. van den, Fransen, J.A.M., and Cambi, A.
- Abstract
Contains fulltext : 282464.pdf (Publisher’s version ) (Open Access)
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- 2022
Catalog
3. Modular actin nano-architecture enables podosome protrusion and mechanosensing
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van den Dries, K. (Koen), Nahidiazar, L. (Leila), Slotman, J.A. (Johan A.), Meddens, M.B.M. (Marjolein B M), Pandzic, E. (Elvis), Joosten, B. (Ben), Ansems, M. (Marleen), Schouwstra, J. (Joost), Meijer, A. (Anke), Steen, R. (Raymond), Wijers, M. (Mietske), Fransen, J.A.M. (Jack), Houtsmuller, A.B. (Adriaan), Wiseman, P.W. (Paul W.), Jalink, K. (Kees), Cambi, A. (Alessandra), van den Dries, K. (Koen), Nahidiazar, L. (Leila), Slotman, J.A. (Johan A.), Meddens, M.B.M. (Marjolein B M), Pandzic, E. (Elvis), Joosten, B. (Ben), Ansems, M. (Marleen), Schouwstra, J. (Joost), Meijer, A. (Anke), Steen, R. (Raymond), Wijers, M. (Mietske), Fransen, J.A.M. (Jack), Houtsmuller, A.B. (Adriaan), Wiseman, P.W. (Paul W.), Jalink, K. (Kees), and Cambi, A. (Alessandra) more...
- Abstract
Basement membrane transmigration during embryonal development, tissue homeostasis and tumor invasion relies on invadosomes, a collective term for invadopodia and podosomes. An adequate structural framework for this process is still missing. Here, we reveal the modular actin nano-architecture that enables podosome protrusion and mechanosensing. The podosome protrusive core contains a central branched actin module encased by a linear actin module, each harboring specific actin interactors and actin isoforms. From the core, two actin modules radiate: ventral filaments bound by vinculin and connected to the plasma membrane and dorsal interpodosomal filaments crosslinked by myosin IIA. On stiff substrates, the actin modules mediate long-range substrate exploration, associated with degradative behavior. On compliant substrates, the vinculin-bound ventral actin filaments shorten, resulting in short-range connectivity and a focally protrusive, non-degradative state. Our findings redefine podosome nanoscale architecture and reveal a paradigm for how actin modularity drives invadosome mechanosensing in cells that breach tissue boundaries. more...
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- 2019
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4. Microbial stimulation of different Toll-like receptor signalling pathways induces diverse metabolic programmes in human monocytes
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Lachmandas, E.L., Boutens, L., Ratter, JM, Hijmans, A., Hooiveld, G.J., Joosten, L.A.B., Rodenburg, R.J.T., Fransen, J.A.M., Houtkooper, R.H., Crevel, R. van, Netea, M.G., Stienstra, R., Lachmandas, E.L., Boutens, L., Ratter, JM, Hijmans, A., Hooiveld, G.J., Joosten, L.A.B., Rodenburg, R.J.T., Fransen, J.A.M., Houtkooper, R.H., Crevel, R. van, Netea, M.G., and Stienstra, R. more...
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Contains fulltext : 170968.pdf (publisher's version ) (Closed access), Microbial stimuli such as lipopolysaccharide (LPS) induce robust metabolic rewiring in immune cells known as the Warburg effect. It is unknown whether this increase in glycolysis and decrease in oxidative phosphorylation (OXPHOS) is a general characteristic of monocytes that have encountered a pathogen. Using CD14+ monocytes from healthy donors, we demonstrated that most microbial stimuli increased glycolysis, but that only stimulation of Toll-like receptor (TLR) 4 with LPS led to a decrease in OXPHOS. Instead, activation of other TLRs, such as TLR2 activation by Pam3CysSK4 (P3C), increased oxygen consumption and mitochondrial enzyme activity. Transcriptome and metabolome analysis of monocytes stimulated with P3C versus LPS confirmed the divergent metabolic responses between both stimuli, and revealed significant differences in the tricarboxylic acid cycle, OXPHOS and lipid metabolism pathways following stimulation of monocytes with P3C versus LPS. At a functional level, pharmacological inhibition of complex I of the mitochondrial electron transport chain diminished cytokine production and phagocytosis in P3C- but not LPS-stimulated monocytes. Thus, unlike LPS, complex microbial stimuli and the TLR2 ligand P3C induce a specific pattern of metabolic rewiring that involves upregulation of both glycolysis and OXPHOS, which enables activation of host defence mechanisms such as cytokine production and phagocytosis. more...
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- 2016
5. Submembranous recruitment of creatine kinase B supports formation of dynamic actin-based protrusions of macrophages and relies on its C-terminal flexible loop
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Venter, G., Polling, S., Pluk, H., Venselaar, H., Wijers, M.J.P., Willemse, M.P., Fransen, J.A.M., Wieringa, B., Venter, G., Polling, S., Pluk, H., Venselaar, H., Wijers, M.J.P., Willemse, M.P., Fransen, J.A.M., and Wieringa, B. more...
- Abstract
Contains fulltext : 154023.pdf (Publisher’s version ) (Closed access), Subcellular partitioning of creatine kinase contributes to the formation of patterns in intracellular ATP distribution and the fuelling of cellular processes with a high and sudden energy demand. We have previously shown that brain-type creatine kinase (CK-B) accumulates at the phagocytic cup in macrophages where it is involved in the compartmentalized generation of ATP for actin remodeling. Here, we report that CK-B catalytic activity also helps in the formation of protrusive ruffle structures which are actin-dependent and abundant on the surface of both unstimulated and LPS-activated macrophages. Recruitment of CK-B to these structures occurred transiently and inhibition of the enzyme's catalytic activity with cyclocreatine led to a general smoothening of surface morphology as visualized by scanning electron microscopy. Comparison of the dynamics of distribution of YFP-tagged CK-mutants and isoforms by live imaging revealed that amino acid residues in the C-terminal segment (aa positions 323-330) that forms one of the protein's two mobile loops are involved in partitioning over inner regions of the cytosol and nearby sites where membrane protrusions occur during induction of phagocytic cup formation. Although wt CK-B, muscle-type CK (CK-M), and a catalytically dead CK-B-E232Q mutant with intact loop region were normally recruited from the cytosolic pool, no dynamic transition to the phagocytic cup area was seen for the CK-homologue arginine kinase and a CK-B-D326A mutant protein. Bioinformatics analysis helped us to predict that conformational flexibility of the C-terminal loop, independent of conformational changes induced by substrate binding or catalytic activity, is likely involved in exposing the enzyme for binding at or near the sites of membrane protrusion formation. more...
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- 2015
6. The Nucleoporin Can/Nup214 Binds to Both the Cytoplasmic and the Nucleoplasmic Sides of the Nuclear Pore Complex in Overexpressing Cells
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Boer, J.M., Deursen, J.M.A. van, Croes, H.J.E., Fransen, J.A.M., and Grosveld, G.
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GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) - Abstract
Contains fulltext : 24997___.PDF (Publisher’s version ) (Open Access)
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- 1997
7. Polarised expression of human intestinal N-benzoyl-L-tyroxyl-p-aminobenzoic acid hydrolase (human meprin) alpha and beta subunits in Madin-Darby canine kidney cells
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Eldering, J.A., Grunberg, J., Hahn, D., Croes, H.J.E., Fransen, J.A.M., and Sterchi, E.E.
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Item does not contain fulltext
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- 1997
8. Congenital Sucrase-isomaltase deficiency: identification of a glutamine to proline substitution that leads to a transport block of sucrase-isomaltase in a pre-Golgi compartment
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Ouwendijk, J., Moolenaar, E.C., Peters, W.J.M, Hollenberg, C.P., Ginsel, L.A., and Fransen, J.A.M.
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GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) - Abstract
Contains fulltext : 20427___.PDF (Publisher’s version ) (Open Access)
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- 1995
9. Glucose controls morphodynamics of LPS-stimulated macrophages
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Venter-van Helden, G., Oerlemans, F.T.J.J., Wijers, M.J.P., Willemse, M.P., Fransen, J.A.M., Wieringa, B., Venter-van Helden, G., Oerlemans, F.T.J.J., Wijers, M.J.P., Willemse, M.P., Fransen, J.A.M., and Wieringa, B. more...
- Abstract
Contains fulltext : 135905.pdf (publisher's version ) (Open Access), Macrophages constantly undergo morphological changes when quiescently surveying the tissue milieu for signs of microbial infection or damage, or after activation when they are phagocytosing cellular debris or foreign material. These morphofunctional alterations require active actin cytoskeleton remodeling and metabolic adaptation. Here we analyzed RAW 264.7 and Maf-DKO macrophages as models to study whether there is a specific association between aspects of carbohydrate metabolism and actin-based processes in LPS-stimulated macrophages. We demonstrate that the capacity to undergo LPS-induced cell shape changes and to phagocytose complement-opsonized zymosan (COZ) particles does not depend on oxidative phosphorylation activity but is fueled by glycolysis. Different macrophage activities like spreading, formation of cell protrusions, as well as phagocytosis of COZ, were thereby strongly reliant on the presence of low levels of extracellular glucose. Since global ATP production was not affected by rewiring of glucose catabolism and inhibition of glycolysis by 2-deoxy-D-glucose and glucose deprivation had differential effects, our observations suggest a non-metabolic role for glucose in actin cytoskeletal remodeling in macrophages, e.g. via posttranslational modification of receptors or signaling molecules, or other effects on the machinery that drives actin cytoskeletal changes. Our findings impute a decisive role for the nutrient state of the tissue microenvironment in macrophage morphodynamics. more...
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- 2014
10. A study of the coupling between morphodynamics and energy metabolism in macrophages
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Wieringa, B., Fransen, J.A.M., Venter-van Helden, G., Wieringa, B., Fransen, J.A.M., and Venter-van Helden, G.
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Radboud Universiteit Nijmegen, 10 oktober 2014, Promotor : Wieringa, B. Co-promotor : Fransen, J.A.M., Contains fulltext : 130268.pdf (publisher's version ) (Open Access)
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- 2014
11. NAMPT-mediated salvage synthesis of NAD+ controls morphofunctional changes of macrophages
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Venter, G., Oerlemans, F.T.J.J., Willemse, M.P., Wijers, M.J.P., Fransen, J.A.M., Wieringa, B., Venter, G., Oerlemans, F.T.J.J., Willemse, M.P., Wijers, M.J.P., Fransen, J.A.M., and Wieringa, B.
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Contains fulltext : 135974.pdf (publisher's version ) (Open Access), Functional morphodynamic behavior of differentiated macrophages is strongly controlled by actin cytoskeleton rearrangements, a process in which also metabolic cofactors ATP and NAD(H) (i.e. NAD+ and NADH) and NADP(H) (i.e. NADP+ and NADPH) play an essential role. Whereas the link to intracellular ATP availability has been studied extensively, much less is known about the relationship between actin cytoskeleton dynamics and intracellular redox state and NAD+-supply. Here, we focus on the role of nicotinamide phosphoribosyltransferase (NAMPT), found in extracellular form as a cytokine and growth factor, and in intracellular form as one of the key enzymes for the production of NAD+ in macrophages. Inhibition of NAD+ salvage synthesis by the NAMPT-specific drug FK866 caused a decrease in cytosolic NAD+ levels in RAW 264.7 and Maf-DKO macrophages and led to significant downregulation of the glycolytic flux without directly affecting cell viability, proliferation, ATP production capacity or mitochondrial respiratory activity. Concomitant with these differential metabolic changes, the capacity for phagocytic ingestion of particles and also substrate adhesion of macrophages were altered. Depletion of cytoplasmic NAD+ induced cell-morphological changes and impaired early adhesion in phagocytosis of zymosan particles as well as spreading performance. Restoration of NAD+ levels by NAD+, NMN, or NADP+ supplementation reversed the inhibitory effects of FK866. We conclude that direct coupling to local, actin-based, cytoskeletal dynamics is an important aspect of NAD+'s cytosolic role in the regulation of morphofunctional characteristics of macrophages. more...
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- 2014
12. The dendritic cell derived protein DC-STAMP is highly conserved and localizes to the endoplasmic reticulum
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Eleveld-Trancikova, D., Triantis, V., Moulin, V., Looman, M.W.G., Wijers, M., Fransen, J.A.M., Lemckert, A.A.C., Havenga, M.J.E., Figdor, C.G., Janssen, R.A.J., and Adema, G.J.
- Abstract
Contains fulltext : 27307.pdf (Publisher’s version ) (Closed access)
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- 2005
13. Cloning and characterization of mCRIP2, a mouse LIM-only protein that interacts with PDZ domain IV of PTP-BL
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Ham, M.A.P.C. van, Croes, H.J.E., Schepens, J.T.G., Fransen, J.A.M., Wieringa, B., and Hendriks, W.J.A.J.
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Neuromuscular development and genetic disorders [UMCN 3.1] - Abstract
Item does not contain fulltext BACKGROUND: In the mouse submembranous protein tyrosine phosphatase PTP-BL five PDZ domains are present in between the N-terminal FERM domain, which directs the protein to the cell cortex, and the C-terminal catalytic phosphatase domain. To understand more on the physical role of PTP-BL in this microenvironment, we started to search for PTP-BL PDZ domain-interacting proteins. RESULTS: Yeast two-hybrid screening for PTP-BL targets resulted in the identification of a novel mouse LIM-only protein termed CRIP2 that is highly homologous to rat ESP1 and human CRP2 sequences. Mouse CRIP2 has a predicted molecular weight of 23 kD and consists of two LIM domains spaced by 68 amino acids. The fourth PDZ domain of PTP-BL is responsible for the binding of CRIP2 protein. Both PTP-BL and CRIP2 mRNAs display a wide, overlapping tissue distribution. Western blot analysis revealed a more restricted expression pattern for CRIP2 with high expression in lung, heart and brain. CRIP2 protein is localized at cell cortical, actin-rich structures, which is concurrent with the subcellular localization of PTP-BL. CONCLUSIONS: The observed characteristics of the LIM domain-containing adaptor protein CRIP2 are consistent with a potential role of PTP-BL in the dynamics of the cortical actin cytoskeleton. more...
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- 2003
14. Decision-support in rheumatoid arthritis
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Fransen, J.A.M., Riel, P.L.C.M. van, Stucki, G., Michel, B.A., and Radboud University Nijmegen
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Chronic inflammation and autoimmunity [UMCN 4.2] - Abstract
Item does not contain fulltext KUN, 08 mei 2003 Promotores : Riel, P.L.C.M. van, Stucki, G., Michel, B.A.
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- 2003
15. Design and analysis of effects of triplet repeat oligonucleotides in cell models for myotonic dystrophy
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Gonzalez-Barriga, A., Mulders, S.A.M., Giessen, J. van der, Hooijer, J.D., Bijl, S., Kessel, I.D.G. van, Beers, J. van, Deutekom, J.C. van, Fransen, J.A.M., Wieringa, B., Wansink, D.G., Gonzalez-Barriga, A., Mulders, S.A.M., Giessen, J. van der, Hooijer, J.D., Bijl, S., Kessel, I.D.G. van, Beers, J. van, Deutekom, J.C. van, Fransen, J.A.M., Wieringa, B., and Wansink, D.G. more...
- Abstract
Contains fulltext : 118254.pdf (publisher's version ) (Open Access), Myotonic dystrophy type 1 (DM1) is caused by DM protein kinase (DMPK) transcripts containing an expanded (CUG)n repeat. Antisense oligonucleotide (AON)-mediated suppression of these mutant RNAs is considered a promising therapeutic strategy for this severe disorder. Earlier, we identified a 2'-O-methyl (2'-OMe) phosphorothioate (PT)-modified (CAG)7 oligo (PS58), which selectively silences mutant DMPK transcripts through recognition of the abnormally long (CUG)n tract. We present here a comprehensive collection of triplet repeat AONs and found that oligo length and nucleotide chemistry are important determinants for activity. For significant reduction of expanded DMPK mRNAs, a minimal length of five triplets was required. 2'-O,4'-C-ethylene-bridged nucleic acid (ENA)-modified AONs appeared not effective, probably due to lack of nuclear internalization. Selectivity for products from the expanded DMPK allele in patient myoblasts, an important requirement to minimize unwanted side effects, appeared also dependent on AON chemistry. In particular, RNase-H-dependent (CAG)n AONs did not show (CUG)n length specificity. We provide evidence that degradation of long DMPK transcripts induced by PS58-type AONs is an RNase-H independent process, does not involve oligo-intrinsic RNase activity nor does it interfere with splicing of DMPK transcripts. Our collection of triplet repeat AONs forms an important resource for further development of a safe therapy for DM1 and other unstable microsatellite diseases.Molecular Therapy-Nucleic Acids (2013) 2, e81; doi:10.1038/mtna.2013.9; published online 19 March 2013. more...
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- 2013
16. Intracellular NAD(H) levels control motility and invasion of glioma cells.
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Horssen, R. van, Willemse, M.P., Haeger, A., Attanasio, F., Guneri, T., Schwab, A., Stock, C.M., Buccione, R., Fransen, J.A.M., Wieringa, B., Horssen, R. van, Willemse, M.P., Haeger, A., Attanasio, F., Guneri, T., Schwab, A., Stock, C.M., Buccione, R., Fransen, J.A.M., and Wieringa, B. more...
- Abstract
01 juni 2013, Contains fulltext : 118678.pdf (publisher's version ) (Closed access), Oncogenic transformation involves reprogramming of cell metabolism, whereby steady-state levels of intracellular NAD(+) and NADH can undergo dramatic changes while ATP concentration is generally well maintained. Altered expression of nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme of NAD(+)-salvage, accompanies the changes in NAD(H) during tumorigenesis. Here, we show by genetic and pharmacological inhibition of NAMPT in glioma cells that fluctuation in intracellular [NAD(H)] differentially affects cell growth and morphodynamics, with motility/invasion capacity showing the highest sensitivity to [NAD(H)] decrease. Extracellular supplementation of NAD(+) or re-expression of NAMPT abolished the effects. The effects of NAD(H) decrease on cell motility appeared parallel coupled with diminished pyruvate-lactate conversion by lactate dehydrogenase (LDH) and with changes in intracellular and extracellular pH. The addition of lactic acid rescued and knockdown of LDH-A replicated the effects of [NAD(H)] on motility. Combined, our observations demonstrate that [NAD(H)] is an important metabolic component of cancer cell motility. Nutrient or drug-mediated modulation of NAD(H) levels may therefore represent a new option for blocking the invasive behavior of tumors. more...
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- 2013
17. Creatine kinase B-driven energy transfer in the brain is important for habituation and spatial learning behaviour, mossy fibre field size and determination of seizure susceptibility
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Jost, C.R., Zee, C.E.E.M. van der, Zandt, H.J.A. in t, Oerlemans, F.T.J.J., Verheij, M.M.M., Streijger, F., Fransen, J.A.M., Deursen, J.M.A. van, Heerschap, A., Cools, A.R., and Wieringa, B.
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Routing of proteins in polarized cells ,Bestudering van abnormale differentiatie en transformatieprocessen bij erfelijke of verworven aandoeningen m.b.v. cel- en diermodellen ,Biomedische Magnetische Resonantie ,Routing van eiwitten in gepolariseerde cellen ,Farmacotherapie van psychomotorische ziektebeelden ,fundamenteel en toegepast onderzoek ,Study of abnormal differentiation and transformation processes in heritable and acquired disorders with the use of cell and animal models ,Pharmacotherapy of psychomotor diseases ,fundamental and applied research ,Biomedical Magnetic Resonance - Abstract
Item does not contain fulltext Creatine kinases are important in maintaining cellular-energy homeostasis, and neuroprotective effects have been attributed to the administration of creatine and creatine-like compounds. Herein we examine whether ablation of the cytosolic brain-type creatine kinase (B-CK) in mice has detrimental effects on brain development, physiological integrity or task performance. Mice deficient in B-CK (B-CK-/-) showed no gross abnormalities in brain anatomy or mitochondrial ultrastructure, but had a larger intra- and infrapyramidal mossy fibre area. Nuclear magnetic resonance spectroscopy revealed that adenosine triphosphate (ATP) and phosphocreatine (PCr) levels were unaffected, but demonstrated an apparent reduction of the PCr left arrow over right arrow ATP phosphorus exchange capacity in these mice. When assessing behavioural characteristics B-CK-/- animals showed diminished open-field habituation. In the water maze, adult B-CK-/- mice were slower to learn, but acquired the spatial task. This task performance deficit persisted in 24-month-old, aged B-CK-/- mice, on top of the age-related memory decline normally seen in old animals. Finally, a delayed development of pentylenetetrazole-induced seizures (creating a high-energy demand) was observed in B-CK-/- mice. It is suggested that the persistent expression of the mitochondrial isoform ubiquitous mitochondrial CK (UbCKmit) in the creatine/phospho-creatine shuttle provides compensation for the loss of B-CK in the brain. Our studies indicate a role for the creatine-phosphocreatine/CK circuit in the formation or maintenance of hippocampal mossy fibre connections, and processes that involve habituation, spatial learning and seizure susceptibility. However, for fuelling of basic physiological activities the role of B-CK can be compensated for by other systems in the versatile and robust metabolic-energy network of the brain. more...
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- 2002
18. DMPK isoforms in muscle and brain cells. Localization and function.
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Wieringa, B., Wansink, D.G., Fransen, J.A.M., Oude Ophuis, R.J.A., Wieringa, B., Wansink, D.G., Fransen, J.A.M., and Oude Ophuis, R.J.A.
- Abstract
Radboud Universiteit Nijmegen, 01 april 2011, Promotor : Wieringa, B. Co-promotores : Wansink, D.G., Fransen, J.A.M., Contains fulltext : 85871.pdf (publisher's version ) (Open Access)
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- 2011
19. The mouse Ptprr gene encodes two protein tyrosine phosphatases, PTP-SL and PTPBR7 that display distinct patterns of expression during neural development
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Maagdenberg, A.M.J.M. van den, Bachner, D., Schepens, J.T.G., Peters, W.J.M, Fransen, J.A.M., Wieringa, B., and Hendriks, W.J.A.J.
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The role of protein-tyrosine phosphatase genes, encoding potential tumor suppressors, in tumor initiation and progression ,Intracellulair transport van glycoprotëinen in gepolariseerde epitheelcellen epitheelcellen ,Intracellular transport of glycoproteins in polarized epithelial cells ,De rol van submembrane proteine-tyrosine fosfatases potentiële tumor suppressors bij celgroei en differentiatie - Abstract
Item does not contain fulltext 13 p.
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- 1999
20. ATP changes the fluorescence lifetime of cyan fluorescent protein via an interaction with His148
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Borst, J.W., Willemse, M.P., Slijkhuis, R., Krogt, G. van der, Laptenok, S.P., Jalink, K., Wieringa, B., Fransen, J.A.M., Borst, J.W., Willemse, M.P., Slijkhuis, R., Krogt, G. van der, Laptenok, S.P., Jalink, K., Wieringa, B., and Fransen, J.A.M. more...
- Abstract
Contains fulltext : 87235.pdf (publisher's version ) (Open Access), Recently, we described that ATP induces changes in YFP/CFP fluorescence intensities of Fluorescence Resonance Energy Transfer (FRET) sensors based on CFP-YFP. To get insight into this phenomenon, we employed fluorescence lifetime spectroscopy to analyze the influence of ATP on these fluorescent proteins in more detail. Using different donor and acceptor pairs we found that ATP only affected the CFP-YFP based versions. Subsequent analysis of purified monomers of the used proteins showed that ATP has a direct effect on the fluorescence lifetime properties of CFP. Since the fluorescence lifetime analysis of CFP is rather complicated by the existence of different lifetimes, we tested a variant of CFP, i.e. Cerulean, as a monomer and in our FRET constructs. Surprisingly, this CFP variant shows no ATP concentration dependent changes in the fluorescence lifetime. The most important difference between CFP and Cerulean is a histidine residue at position 148. Indeed, changing this histidine in CFP into an aspartic acid results in identical fluorescence properties as observed for the Cerulean fluorescent based FRET sensor. We therefore conclude that the changes in fluorescence lifetime of CFP are affected specifically by possible electrostatic interactions of the negative charge of ATP with the positively charged histidine at position 148. Clearly, further physicochemical characterization is needed to explain the sensitivity of CFP fluorescence properties to changes in environmental (i.e. ATP concentrations) conditions. more...
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- 2010
21. Advantages of indium-tin oxide-coated glass slides in correlative scanning electron microscopy applications of uncoated cultured cells.
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Pluk, H., Stokes, D.J., Lich, B., Wieringa, B., Fransen, J.A.M., Pluk, H., Stokes, D.J., Lich, B., Wieringa, B., and Fransen, J.A.M.
- Abstract
Contains fulltext : 79890.pdf (publisher's version ) (Closed access), A method of direct visualization by correlative scanning electron microscopy (SEM) and fluorescence light microscopy of cell structures of tissue cultured cells grown on conductive glass slides is described. We show that by growing cells on indium-tin oxide (ITO)-coated glass slides, secondary electron (SE) and backscatter electron (BSE) images of uncoated cells can be obtained in high-vacuum SEM without charging artefacts. Interestingly, we observed that BSE imaging is influenced by both accelerating voltage and ITO coating thickness. By combining SE and BSE imaging with fluorescence light microscopy imaging, we were able to reveal detailed features of actin cytoskeletal and mitochondrial structures in mouse embryonic fibroblasts. We propose that the application of ITO glass as a substrate for cell culture can easily be extended and offers new opportunities for correlative light and electron microscopy studies of adherently growing cells. more...
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- 2009
22. Increased OXPHOS activity precedes rise in glycolytic rate in H-RasV12/E1A transformed fibroblasts that develop a Warburg phenotype.
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Groof, A.J.C. de, Lindert, M.M. te, Dommelen, M.M.T. van, Wu, M., Willemse, M.P., Smift, A.L., Winer, M., Oerlemans, F.T.J.J., Pluk, H., Fransen, J.A.M., Wieringa, B., Groof, A.J.C. de, Lindert, M.M. te, Dommelen, M.M.T. van, Wu, M., Willemse, M.P., Smift, A.L., Winer, M., Oerlemans, F.T.J.J., Pluk, H., Fransen, J.A.M., and Wieringa, B. more...
- Abstract
Contains fulltext : 80248.pdf (publisher's version ) (Open Access), BACKGROUND: The Warburg phenotype in cancer cells has been long recognized, but there is still limited insight in the consecutive metabolic alterations that characterize its establishment. We obtained better understanding of the coupling between metabolism and malignant transformation by studying mouse embryonic fibroblast-derived cells with loss-of-senescence or H-RasV12/E1A-transformed phenotypes at different stages of oncogenic progression. RESULTS: Spontaneous immortalization or induction of senescence-bypass had only marginal effects on metabolic profiles and viability. In contrast, H-RasV12/E1A transformation initially caused a steep increase in oxygen consumption and superoxide production, accompanied by massive cell death. During prolonged culture in vitro, cell growth rate increased gradually, along with tumor forming potential in in vitro anchorage-independent growth assays and in vivo tumor formation assays in immuno-deficient mice. Notably, glucose-to-lactic acid flux increased with passage number, while cellular oxygen consumption decreased. This conversion in metabolic properties was associated with a change in mitochondrial NAD+/NADH redox, indicative of decreased mitochondrial tricarboxic acid cycle and OXPHOS activity. CONCLUSION: The high rate of oxidative metabolism in newly transformed cells is in marked contrast with the high glycolytic rate in cells in the later tumor stage. In our experimental system, with cells growing under ambient oxygen conditions in nutrient-rich media, the shift towards this Warburg phenotype occurred as a step-wise adaptation process associated with augmented tumorigenic capacity and improved survival characteristics of the transformed cells. We hypothesize that early-transformed cells, which potentially serve as founders for new tumor masses may escape therapies aimed at metabolic inhibition of tumors with a fully developed Warburg phenotype. more...
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- 2009
23. Local ATP generation by brain-type creatine kinase (CK-B) facilitates cell motility
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Kuiper, J.W.P., Horssen, R. van, Oerlemans, F.T.J.J., Peters, W.J.M, Dommelen, M.M.T. van, Lindert, M.M. te, Hagen, T.L.M. ten, Janssen, E.E.W., Fransen, J.A.M., Wieringa, B., Kuiper, J.W.P., Horssen, R. van, Oerlemans, F.T.J.J., Peters, W.J.M, Dommelen, M.M.T. van, Lindert, M.M. te, Hagen, T.L.M. ten, Janssen, E.E.W., Fransen, J.A.M., and Wieringa, B. more...
- Abstract
Contains fulltext : 76049.pdf (publisher's version ) (Open Access), BACKGROUND: Creatine Kinases (CK) catalyze the reversible transfer of high-energy phosphate groups between ATP and phosphocreatine, thereby playing a storage and distribution role in cellular energetics. Brain-type CK (CK-B) deficiency is coupled to loss of function in neural cell circuits, altered bone-remodeling by osteoclasts and complement-mediated phagocytotic activity of macrophages, processes sharing dependency on actomyosin dynamics. METHODOLOGY/PRINCIPAL FINDINGS: Here, we provide evidence for direct coupling between CK-B and actomyosin activities in cortical microdomains of astrocytes and fibroblasts during spreading and migration. CK-B transiently accumulates in membrane ruffles and ablation of CK-B activity affects spreading and migration performance. Complementation experiments in CK-B-deficient fibroblasts, using new strategies to force protein relocalization from cytosol to cortical sites at membranes, confirmed the contribution of compartmentalized CK-B to cell morphogenetic dynamics. CONCLUSION/SIGNIFICANCE: Our results provide evidence that local cytoskeletal dynamics during cell motility is coupled to on-site availability of ATP generated by CK-B. more...
- Published
- 2009
24. PTPRR protein tyrosine phosphatase isoforms and locomotion of vesicles and mice.
- Author
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Hendriks, W.J.A.J., Dilaver, G., Noordman, Y.E., Kremer, H.P.H., Fransen, J.A.M., Hendriks, W.J.A.J., Dilaver, G., Noordman, Y.E., Kremer, H.P.H., and Fransen, J.A.M.
- Abstract
Contains fulltext : 81710.pdf (publisher's version ) (Closed access), Protein tyrosine phosphatases (PTPs) are central players in many different cellular processes and their aberrant activity is associated with multiple human pathologies. In this review, we present current knowledge on the PTPRR subfamily of classical PTPs that is expressed in neuronal cells and comprises receptor-type (PTPBR7, PTP-SL) as well as cytosolic (PTPPBSgamma-37, PTPPBSgamma-42) isoforms. The two receptor-type isoforms PTPBR7 and PTP-SL both localize in late endosomes and the Golgi area. PTPBR7, however, is additionally localized at the cell surface and on early endosomes. During cerebellar maturation, PTPBR7 expression in developing Purkinje cells ceases and is replaced by PTP-SL expression in the mature Purkinje cells. All PTPRR isoforms contain a kinase interacting motif that makes them mitogen-activated protein kinase phosphatases. The distinct subcellular localization of the different PTPRR isoforms may reflect differential roles in growth-factor-induced MAPK-mediated retrograde signaling cascades. Studies in PTPRR-deficient mice established that PTPRR isoforms are physiological regulators of MAPK phosphorylation levels. Surprisingly, PTPRR-deficient mice display defects in motor coordination and balancing skills, while cerebellar morphological abnormalities, which are often encountered in ataxic mouse models, are absent. This is reminiscent of the phenotype observed in a handful of mouse mutants that have alterations in cerebellar calcium ion homeostasis. Elucidation of the molecular mechanisms by which PTPRR deficiency imposes impairment of cerebellar neurons and motor coordination may provide candidate molecules for hereditary cerebellar ataxias that still await identification of the corresponding disease genes. more...
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- 2009
25. Modulation of cell motility by spatial repositioning of enzymatic ATP/ADP exchange capacity.
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Horssen, R. van, Janssen, E.E.W., Peters, W.J.M, Pasch, L. van de, Lindert, M.M. te, Dommelen, M.M.T. van, Linssen, P.C.M., Hagen, T.L.M. ten, Fransen, J.A.M., Wieringa, B., Horssen, R. van, Janssen, E.E.W., Peters, W.J.M, Pasch, L. van de, Lindert, M.M. te, Dommelen, M.M.T. van, Linssen, P.C.M., Hagen, T.L.M. ten, Fransen, J.A.M., and Wieringa, B. more...
- Abstract
Contains fulltext : 79636.pdf (Publisher’s version ) (Open Access), ATP is the "principal energy currency" in metabolism and the most versatile small molecular regulator of cellular activities. Although already much is known about the role of ATP in fundamental processes of living systems, data about its compartmentalization are rather scarce, and we still have only very limited understanding of whether patterns in the distribution of intracellular ATP concentration ("ATP inhomogeneity") do exist and have a regulatory role. Here we report on the analysis of coupling of local ATP supply to regulation of actomyosin behavior, a widespread and dynamic process with conspicuous high ATP dependence, which is central to cell shape changes and cell motility. As an experimental model, we use embryonic fibroblasts from knock-out mice without major ATP-ADP exchange enzymes, in which we (re)introduce the ATP/ADP exchange enzyme adenylate kinase-1 (AK1) and deliberately manipulate its spatial positioning by coupling to different artificial location tags. By transfection-complementation of AK1 variants and comparison with yellow fluorescent protein controls, we found that motility and spreading were enhanced in cells with AK1 with a focal contact guidance tag. Intermediary enhancement was observed in cells with membrane-targeted or cytosolic AK1. Use of a heterodimer-inducing approach for transient translocation of AK1 to focal contacts under conditions of constant global AK1 activity in the cell corroborated these results. Based on our findings with these model systems, we propose that local ATP supply in the cell periphery and "on site" fuelling of the actomyosin machinery, when maintained via enzymes involved in phosphoryl transfer, are codetermining factors in the control of cell motility. more...
- Published
- 2009
26. Local ATP generation by brain-type creatine kinase (CK-B) facilities cell motility
- Author
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Kuiper, J.W.P. (Jan), Horssen, R. (Remco) van, Oerlemans, F. (Frank), Peters, W. (Wilma), Dommelen, M.M.T. (Michiel) van, Lindert, M.M. (Mariska) te, Hagen, T.L.M. (Timo) ten, Janssen, E. (Edwin), Fransen, J.A.M. (Jack), Wieringa, B. (Bé), Kuiper, J.W.P. (Jan), Horssen, R. (Remco) van, Oerlemans, F. (Frank), Peters, W. (Wilma), Dommelen, M.M.T. (Michiel) van, Lindert, M.M. (Mariska) te, Hagen, T.L.M. (Timo) ten, Janssen, E. (Edwin), Fransen, J.A.M. (Jack), and Wieringa, B. (Bé) more...
- Abstract
Background: Creatine Kinases (CK) catalyze the reversible transfer of high-energy phosphate groups between ATP and phosphocreatine, thereby playing a storage and distribution role in cellular energetics. Brain-type CK (CK-B) deficiency is coupled to loss of function in neural cell circuits, altered bone-remodeling by osteoclasts and complement-mediated phagocytotic activity of macrophages, processes sharing dependency on actomyosin dynamics. Methodology/Principal Findings: Here, we provide evidence for direct coupling between CK-B and actomyosin activities in cortical microdomains of astrocytes and fibroblasts during spreading and migration. CK-B transiently accumulates in membrane ruffles and ablation of CK-B activity affects spreading and migration performance. Complementation experiments in CK-B-deficient fibroblasts, using new strategies to force protein relocalization from cytosol to cortical sites at membranes, confirmed the contribution of compartmentalized CK-B to cell morphogenetic dynamics. Conclusion/Significance: Our results provide evidence that local cytoskeletal dynamics during cell motility is coupled to on-site availability of ATP generated by CK-B. more...
- Published
- 2009
- Full Text
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27. The C-type lectin DC-SIGN internalizes soluble antigens and HIV-1 virions via a clathrin-dependent mechanism.
- Author
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Cambi, A., Beeren, I.M.J., Joosten, B.H.G.M., Fransen, J.A.M., Figdor, C.G., Cambi, A., Beeren, I.M.J., Joosten, B.H.G.M., Fransen, J.A.M., and Figdor, C.G.
- Abstract
Contains fulltext : 81388.pdf (publisher's version ) (Closed access), Dendritic cells (DC), professional Ag-presenting cells located in mucosae and lymphoid organs, operate at the interface of innate and adaptive immunity and are likely the first cells to encounter invading HIV-1. Although the C-type lectin DC-Specific ICAM-3-grabbing non-integrin (DC-SIGN) binds to several viruses, including HIV-1, its direct involvement in viral entry remains controversial. Despite its central role in DC function, little is known about the underlying molecular mechanism(s) of DC-SIGN-mediated Ag uptake. Here, we analyzed the early stages of DC-SIGN-mediated endocytosis and demonstrate that both membrane cholesterol and dynamin are required. Confocal microscopy and clathrin RNAi showed that DC-SIGN-mediated internalization occurs via clathrin-coated pits. Electron microscopy of ultrathin sections showed the involvement of DC-SIGN in clathrin-dependent HIV-1 internalization by DC. Currently, DC-specific C-type lectins are considered potential target in anti-tumor clinical trials. Detailed information about how different Ag are internalized via these receptors will facilitate the rational design of targeted therapeutic strategies. more...
- Published
- 2009
28. Subunits of mitochondrial complex I exist as part of matrix- and membrane-associated subcomplexes in living cells.
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Dieteren, C.E.J., Willems, P.H.G.M., Vogel, R.O., Swarts, H.G.P., Fransen, J.A.M., Roepman, R., Crienen, G., Smeitink, J.A.M., Nijtmans, L.G.J., Koopman, W.J.H., Dieteren, C.E.J., Willems, P.H.G.M., Vogel, R.O., Swarts, H.G.P., Fransen, J.A.M., Roepman, R., Crienen, G., Smeitink, J.A.M., Nijtmans, L.G.J., and Koopman, W.J.H. more...
- Abstract
Contains fulltext : 70919.pdf (Publisher’s version ) (Open Access), Mitochondrial complex I (CI) is a large assembly of 45 different subunits, and defects in its biogenesis are the most frequent cause of mitochondrial disorders. In vitro evidence suggests a stepwise assembly process involving pre-assembled modules. However, whether these modules also exist in vivo is as yet unresolved. To answer this question, we here applied submitochondrial fluorescence recovery after photobleaching to HEK293 cells expressing 6 GFP-tagged subunits selected on the basis of current CI assembly models. We established that each subunit was partially present in a virtually immobile fraction, possibly representing the holo-enzyme. Four subunits (NDUFV1, NDUFV2, NDUFA2, and NDUFA12) were also present as highly mobile matrix-soluble monomers, whereas, in sharp contrast, the other two subunits (NDUFB6 and NDUFS3) were additionally present in a slowly mobile fraction. In the case of the integral membrane protein NDUFB6, this fraction most likely represented one or more membrane-bound subassemblies, whereas biochemical evidence suggested that for the NDUFS3 protein this fraction most probably corresponded to a matrix-soluble subassembly. Our results provide first time evidence for the existence of CI subassemblies in mitochondria of living cells. more...
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- 2008
29. Inherited complex I deficiency is associated with faster protein diffusion in the matrix of moving mitochondria.
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Koopman, W.J.H., Distelmaier, F., Hink, M.A., Verkaart, S.A.J., Wijers-Rouw, M.J.P., Fransen, J.A.M., Smeitink, J.A.M., Willems, P.H.G.M., Koopman, W.J.H., Distelmaier, F., Hink, M.A., Verkaart, S.A.J., Wijers-Rouw, M.J.P., Fransen, J.A.M., Smeitink, J.A.M., and Willems, P.H.G.M. more...
- Abstract
Contains fulltext : 69710.pdf (publisher's version ) (Closed access), Mitochondria continuously change shape, position, and matrix configuration for optimal metabolite exchange. It is well established that changes in mitochondrial metabolism influence mitochondrial shape and matrix configuration. We demonstrated previously that inhibition of mitochondrial complex I (CI or NADH:ubiquinone oxidoreductase) by rotenone accelerated matrix protein diffusion and decreased the fraction and velocity of moving mitochondria. In the present study, we investigated the relationship between inherited CI deficiency, mitochondrial shape, mobility, and matrix protein diffusion. To this end, we analyzed fibroblasts of two children that represented opposite extremes in a cohort of 16 patients, with respect to their residual CI activity and mitochondrial shape. Fluorescence correlation spectroscopy (FCS) revealed no relationship between residual CI activity, mitochondrial shape, the fraction of moving mitochondria, their velocity, and the rate of matrix-targeted enhanced yellow fluorescent protein (mitoEYFP) diffusion. However, mitochondrial velocity and matrix protein diffusion in moving mitochondria were two to three times higher in patient cells than in control cells. Nocodazole inhibited mitochondrial movement without altering matrix EYFP diffusion, suggesting that both activities are mutually independent. Unexpectedly, electron microscopy analysis revealed no differences in mitochondrial ultrastructure between control and patient cells. It is discussed that the matrix of a moving mitochondrion in the CI-deficient state becomes less dense, allowing faster metabolite diffusion, and that fibroblasts of CI-deficient patients become more glycolytic, allowing a higher mitochondrial velocity. more...
- Published
- 2008
30. Creatine kinase-mediated ATP supply fuels actin-based events in phagocytosis.
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Kuiper, J.W.P., Pluk, H., Oerlemans, F.T.J.J., Leeuwen, F.N. van, Lange, F. de, Fransen, J.A.M., Wieringa, B., Kuiper, J.W.P., Pluk, H., Oerlemans, F.T.J.J., Leeuwen, F.N. van, Lange, F. de, Fransen, J.A.M., and Wieringa, B. more...
- Abstract
Contains fulltext : 69424.pdf ( ) (Open Access), Phagocytosis requires locally coordinated cytoskeletal rearrangements driven by actin polymerization and myosin motor activity. How this actomyosin dynamics is dependent upon systems that provide access to ATP at phagosome microdomains has not been determined. We analyzed the role of brain-type creatine kinase (CK-B), an enzyme involved in high-energy phosphoryl transfer. We demonstrate that endogenous CK-B in macrophages is mobilized from the cytosolic pool and coaccumulates with F-actin at nascent phagosomes. Live cell imaging with XFP-tagged CK-B and beta-actin revealed the transient and specific nature of this partitioning process. Overexpression of a catalytic dead CK-B or CK-specific cyclocreatine inhibition caused a significant reduction of actin accumulation in the phagocytic cup area, and reduced complement receptor-mediated, but not Fc-gammaR-mediated, ingestion capacity of macrophages. Finally, we found that inhibition of CK-B affected phagocytosis already at the stage of particle adhesion, most likely via effects on actin polymerization behavior. We propose that CK-B activity in macrophages contributes to complement-induced F-actin assembly events in early phagocytosis by providing local ATP supply. more...
- Published
- 2008
31. Rab proteins specify motorized vesicle transport.
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Wieringa, B., Fransen, J.A.M., Wanschers, B.F.J., Wieringa, B., Fransen, J.A.M., and Wanschers, B.F.J.
- Abstract
RU Radboud Universiteit Nijmegen, 29 mei 2008, Promotor : Wieringa, B. Co-promotor : Fransen, J.A.M., Contains fulltext : 71292.pdf (publisher's version ) (Open Access), Small GTPases of the Rab-family are key regulators of intracellular membrane traffic. These proteins constantly cycle between an 'active' GTP-bound and 'inactive' GDP-bound state. In their GTP-bound conformation Rab proteins can engage in complex formation with so called effector proteins. It is at this level that the control of membrane transport is exerted. To date more than 60 Rab-family members, including isoforms, are recognized. To this family also belongs the Golgi-localized Rab6. In the past three different isoforms of this protein were identified: Rab6A, Rab6A'(generated by alternative splicing of a homologues but distinct exon within the Rab6 gene), and a brain specific isoform, Rab6B. Rab6A' is the isoform regulating the entire retrograde pathway from late endosomes to ER, whereas Rab6A seems dispensable for this route. The role of Rab6B is still ill-defined and therefore the main focus of this study. Studies using GFP-Rab6B in neuronal cells revealed the bi-directional movement of Rab6B positive structures in neurites of these cells, possibly belonging to the post-Golgi compartment. This latter finding was corroborated with a tsVSVG-assay, which localized Rab6B on vesicles moving from the Golgi towards the plasma membrane. Furthermore we also found co-localization of Rab6B with vesicles containing internalized GPI-anchored proteins. A regulatory role for Rab6B in the internalization of these proteins can therefore be anticipated. To learn more about the molecular environment of Rab6B we searched for novel Rab6B interacting proteins. Of the newly identified Rab6B interactors two were analyzed in more detail, namely Bicaudal-D1 and DYNLRB1. Whereas Bicaudal-D1 provides an indirect binding of Rab6B to the dynein/dynactin motor protein complex, DYNLRB1 assures direct binding. Dynein/dynactin is the main microtubule based motor protein complex responsible for long range retrograde transport. Based on our findings we expect an important role for Rab6B in regul more...
- Published
- 2008
32. Creatine kinase B deficient neurons exhibit an increased fraction of motile mitochondria.
- Author
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Kuiper, J.W.P., Oerlemans, F.T.J.J., Fransen, J.A.M., Wieringa, B., Kuiper, J.W.P., Oerlemans, F.T.J.J., Fransen, J.A.M., and Wieringa, B.
- Abstract
Contains fulltext : 69450.pdf ( ) (Open Access), BACKGROUND: Neurons require an elaborate system of intracellular transport to distribute cargo throughout axonal and dendritic projections. Active anterograde and retrograde transport of mitochondria serves in local energy distribution, but at the same time also requires input of ATP. Here we studied whether brain-type creatine kinase (CK-B), a key enzyme for high-energy phosphoryl transfer between ATP and CrP in brain, has an intermediary role in the reciprocal coordination between mitochondrial motility and energy distribution. Therefore, we analysed the impact of brain-type creatine kinase (CK-B) deficiency on transport activity and velocity of mitochondria in primary murine neurons and made a comparison to the fate of amyloid precursor protein (APP) cargo in these cells, using live cell imaging. RESULTS: Comparison of average and maximum transport velocities and global transport activity showed that CK-B deficiency had no effect on speed of movement of mitochondria or APP cargo, but that the fraction of motile mitochondria was significantly increased by 36% in neurons derived from CK-B knockout mice. The percentage of motile APP vesicles was not altered. CONCLUSION: CK-B activity does not directly couple to motor protein activity but cells without the enzyme increase the number of motile mitochondria, possibly as an adaptational strategy aimed to enhance mitochondrial distribution versatility in order to compensate for loss of efficiency in the cellular network for ATP distribution. more...
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- 2008
33. Rab6 family proteins interact with the dynein light chain protein DYNLRB1.
- Author
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Wanschers, B.F.J., Vorstenbosch, R.A. van de, Wijers-Rouw, M.J.P., Wieringa, B., King, S.M., Fransen, J.A.M., Wanschers, B.F.J., Vorstenbosch, R.A. van de, Wijers-Rouw, M.J.P., Wieringa, B., King, S.M., and Fransen, J.A.M. more...
- Abstract
Contains fulltext : 71249.pdf (publisher's version ) (Closed access), The small GTPase Rab6 is a key regulator in the retrograde transfer from endosomes via the Golgi to the ER. Three isoforms of Rab6 have been identified, the ubiquitously expressed Rab6A and Rab6A', and the brain specific Rab6B. Recent studies have shown that Rab6A' is the major isoform regulating this retrograde transport. Cytoplasmic dynein is the main motor protein complex for this transport. Dynein consists of two heavy chains, two intermediate chains, four light intermediate chains and several light chains, called roadblock/LC7 proteins or DYNLRB proteins. In mammalian cells two light chain isoforms have been identified, DYNLRB1 and DYNLRB2. We here show with yeast-two-hybrid, co-immunoprecipitation and pull down studies that DYNLRB1 specifically interacts with all three Rab6 isoforms and co-localises at the Golgi. This is the first example of a direct interaction between Rab6 isoforms and the dynein complex. Pull down experiments showed further preferred association of DYNLRB1 with GTP-bound Rab6A and interestingly GDP-bound Rab6A' and Rab6B. In addition DYNLRB1 was found in the Golgi apparatus where it co-localises with EYFP-Rab6 isoforms. DYNLRB is a putative modulator of the intrinsic GTPase activity of GTP-binding proteins. In vitro we were not able to reproduce this effect on Rab6 GTPase activity. more...
- Published
- 2008
34. Cysts of PRKCSH mutated polycystic liver disease patients lack hepatocystin but express Sec63p.
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Waanders, E., Croes, H.J.E., Maass, C.N., Morsche, R.H.M. te, Geffen, H.J.J.A., Krieken, J.H.J.M. van, Fransen, J.A.M., Drenth, J.P.H., Waanders, E., Croes, H.J.E., Maass, C.N., Morsche, R.H.M. te, Geffen, H.J.J.A., Krieken, J.H.J.M. van, Fransen, J.A.M., and Drenth, J.P.H. more...
- Abstract
Contains fulltext : 69124.pdf (publisher's version ) (Closed access), Polycystic liver disease (PCLD) is an inherited disorder caused by mutations in either PRKCSH (hepatocystin) or SEC63 (Sec63p). However, expression patterns of the implicated proteins in diseased and normal liver are unknown. We analyzed subcellular and cellular localization of hepatocystin and Sec63p using cell fractionation, immunofluorescence, and immunohistochemical methods. Expression patterns were assessed in fetal liver, PCLD liver, and normal adult liver. We found hepatocystin and Sec63p expression predominantly in the endoplasmic reticulum. In fetal tissue, there was intense expression of hepatocystin in ductal plate, bile ducts, and hepatocytes. However, Sec63p staining was prominent in early hepatocytes only and weak in bile ducts throughout development. In PCLD tissue, hepatocystin was expressed in hepatocytes, bile ducts, and in cyst epithelium of patients negative for PRKCSH mutation. In contrast, the majority of cysts from PRKCSH mutation carriers did not express hepatocystin. Sec63p expression was observed in all cyst epithelia regardless of mutational state. We conclude that hepatocystin is probably required for development of bile ducts and does not interact with Sec63p. The results support the hypothesis that cyst formation in PCLD results from a cellular recessive mechanism involving loss of hepatocystin. Cystogenesis in SEC63-associated PCLD occurs via a different mechanism. more...
- Published
- 2008
35. Analysis of a naturally occurring mutation in sucrase-isomaltase: glutamine 1098 is not essential for transport to the surface of COS-1 cells
- Author
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Ouwendijk, J., Peters, W.J.M, Morsche, R.H.M. te, Vorstenbosch, R.A. van de, Ginsel, L.A., Naim, H.Y., and Fransen, J.A.M.
- Subjects
a molecular-cell biological [Expression of brush-border and lysosomal enzymes in polarized epithelial cells] ,een molecualir celbiologisch onderzoek [Expressie van brush-border en lysosomale enzymen in gepolariseerde epitheelcellen] - Abstract
Item does not contain fulltext 8 p.
- Published
- 1998
36. A role for the Rab6B Bicaudal-D1 interaction in retrograde transport in neuronal cells.
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Wanschers, B.F.J., Vorstenbosch, R.A. van de, Schlager, M.A., Splinter, D., Akhmanova, A., Hoogenraad, C.C., Wieringa, B., Fransen, J.A.M., Wanschers, B.F.J., Vorstenbosch, R.A. van de, Schlager, M.A., Splinter, D., Akhmanova, A., Hoogenraad, C.C., Wieringa, B., and Fransen, J.A.M. more...
- Abstract
Contains fulltext : 53424.pdf (publisher's version ) (Closed access), The Rab6 subfamily of small GTPases consists of three different isoforms: Rab6A, Rab6A' and Rab6B. Both Rab6A and Rab6A' are ubiquitously expressed whereas Rab6B is predominantly expressed in brain. Recent studies have shown that Rab6A' is the isoform regulating the retrograde transport from late endosomes via the Golgi to the ER and in the transition from anaphase to metaphase during mitosis. Since the role of Rab6B is still ill defined, we set out to characterize its intracellular environment and dynamic behavior. In a Y-2H search for novel Rab6 interacting proteins, we identified Bicaudal-D1, a large coiled-coil protein known to bind to the dynein/dynactin complex and previously shown to be a binding partner for Rab6A/Rab6A'. Co-immunoprecipitation studies and pull down assays confirmed that Bicaudal-D1 also interacts with Rab6B in its active form. Using confocal laser scanning microscopy it was established that Rab6B and Bicaudal-D1 co-localize at the Golgi and vesicles that align along microtubules. Furthermore, both proteins co-localized with dynein in neurites of SK-N-SH cells. Live cell imaging revealed bi-directional movement of EGFP-Rab6B structures in SK-N-SH neurites. We conclude from our data that the brain-specific Rab6B via Bicaudal-D1 is linked to the dynein/dynactin complex, suggesting a regulatory role for Rab6B in the retrograde transport of cargo in neuronal cells. more...
- Published
- 2007
37. ATP and FRET--a cautionary note.
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Willemse, M.P., Janssen, E., Lange, F. de, Wieringa, B., Fransen, J.A.M., Willemse, M.P., Janssen, E., Lange, F. de, Wieringa, B., and Fransen, J.A.M.
- Abstract
Contains fulltext : 53003.pdf (publisher's version ) (Closed access)
- Published
- 2007
38. Polarised expression of human intestinal N-benzoyl-l-tyroxyl-p-aminobenzoic acid hydrolase (human meprin) alpha and beta subunits in Madin Darby canine kidney cells
- Author
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Hahn, A., Croes, H.J.E., and Fransen, J.A.M.
- Subjects
GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) - Abstract
Contains fulltext : 24674___.PDF (Publisher’s version ) (Open Access)
- Published
- 1997
39. Sucrase-isomaltase: A unique model to study specific cell-biological processes
- Author
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Ouwendijk, J., Ginsel, L.A., and Fransen, J.A.M.
- Abstract
Item does not contain fulltext
- Published
- 1997
40. Effects of long-term treatment with low dose corticosteroids on rat diaphragm contractility, immunohistochemistry and biochemistry
- Author
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Balkom, R.H.H. van, Folgering, H.T.M., Moerkerk, H.T.B. van, Veerkamp, J.H., Fransen, J.A.M., Ginsel, L.A., Herwaarden, C.L.A. van, and Dekhuijzen, P.N.R.
- Subjects
Effecten van corticosteroiden op het diafragma van normale en emfysemateuze dieren ,Effects of corticosteroids on the diaphragm of normal and emphysematous animals - Abstract
Item does not contain fulltext
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- 1997
41. A mutation in a highly conserved region in brush-border sucrase-isomaltase and lysosomal alpha-glucosidase results in Golgi retention
- Author
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Moolenaar, C.E.C., Ouwendijk, J., Wittpoth, M., Wisselaar, H.A., Hauri, H.P., Ginsel, L.A., Naim, H.Y., Fransen, J.A.M., and Clinical Genetics
- Subjects
GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) - Abstract
Contains fulltext : 27832___.PDF (Publisher’s version ) (Open Access)
- Published
- 1997
42. Organization of the integrin LFA-1 in nanoclusters regulates its activity.
- Author
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Cambi, A., Joosten, B.H.G.M., Koopman, M., Lange, F. de, Beeren, I.M.J., Torensma, R., Fransen, J.A.M., Garcia-Parajo, M.F., Leeuwen, F.N. van, Figdor, C.G., Cambi, A., Joosten, B.H.G.M., Koopman, M., Lange, F. de, Beeren, I.M.J., Torensma, R., Fransen, J.A.M., Garcia-Parajo, M.F., Leeuwen, F.N. van, and Figdor, C.G. more...
- Abstract
Contains fulltext : 51243.pdf (publisher's version ) (Open Access), The beta2-integrin LFA-1 facilitates extravasation of monocytes (MOs) into the underlying tissues, where MOs can differentiate into dendritic cells (DCs). Although DCs express LFA-1, unlike MOs, they cannot bind to ICAM-1. We hypothesized that an altered integrin organization on the DC plasma membrane might cause this effect and investigated the relationship between membrane organization and function of LFA-1 on MOs and DCs. High-resolution mapping of LFA-1 surface distribution revealed that on MOs LFA-1 function is associated with a distribution in well-defined nanoclusters (100-150-nm diameter). Interestingly, a fraction of these nanoclusters contains primed LFA-1 molecules expressing the specific activation-dependent L16-epitope. Live imaging of MO-T-cell conjugates showed that only these primed nanoclusters are dynamically recruited to the cellular interface forming micrometer-sized assemblies engaged in ligand binding and linked to talin. We conclude that besides affinity regulation, LFA-1 function is controlled by at least three different avidity patterns: random distributed inactive molecules, well-defined ligand-independent proactive nanoclusters, and ligand-triggered micrometer-sized macroclusters. more...
- Published
- 2006
43. Small GTPase Rab21 regulates cell adhesion and controls endosomal traffic of beta1-integrins.
- Author
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Pellinen, T., Arjonen, A., Vuoriluoto, K., Kallio, K., Fransen, J.A.M., Ivaska, J., Pellinen, T., Arjonen, A., Vuoriluoto, K., Kallio, K., Fransen, J.A.M., and Ivaska, J.
- Abstract
Contains fulltext : 50410.pdf (publisher's version ) (Open Access), Dynamic turnover of integrin cell adhesion molecules to and from the cell surface is central to cell migration. We report for the first time an association between integrins and Rab proteins, which are small GTPases involved in the traffic of endocytotic vesicles. Rab21 (and Rab5) associate with the cytoplasmic domains of alpha-integrin chains, and their expression influences the endo/exocytic traffic of integrins. This function of Rab21 is dependent on its GTP/GDP cycle and proper membrane targeting. Knock down of Rab21 impairs integrin-mediated cell adhesion and motility, whereas its overexpression stimulates cell migration and cancer cell adhesion to collagen and human bone. Finally, overexpression of Rab21 fails to induce cell adhesion via an integrin point mutant deficient in Rab21 association. These data provide mechanistic insight into how integrins are targeted to intracellular compartments and how their traffic regulates cell adhesion. more...
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- 2006
44. Congenital sucrase-isomaltase deficiency : Identification of a glutamine to proline substitution that leads to a transport block of sucrase-isomaltase in a pre-Golgi compartment
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Ouwendijk, J., Moolenaar, C.E.C., Peters, W.J., Hollenberg, C.P., Ginsel, L.A., Fransen, J.A.M., and Naim, H.Y.
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GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) - Abstract
Contains fulltext : 23581___.PDF (Publisher’s version ) (Open Access)
- Published
- 1996
45. Ultrastructural immunogold labeling of lidip-laden enterocytes from patients with genetic malabsorption syndromes
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Ginsel, L.A. and Fransen, J.A.M.
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Intracellulair transport van glycoprotëinen in gepolariseerde epitheelcellen epitheelcellen ,Intracellular transport of glycoproteins in polarized epithelial cells - Abstract
Item does not contain fulltext 7 p.
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- 1996
46. The pro region of human intestinal lactase-phlorizin hydrolase
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Ouwendijk, J., Vorstenbosch, R. van de, Ginsel, L.A., and Fransen, J.A.M.
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Item does not contain fulltext
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- 1996
47. Protein Tyrosine Phospatase PTPRR isoforms in cellular signaling and trafficking.
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Wieringa, B., Fransen, J.A.M., Hendriks, W.J.A.J., Dilaver, G., Wieringa, B., Fransen, J.A.M., Hendriks, W.J.A.J., and Dilaver, G.
- Abstract
RU Radboud Universiteit Nijmegen, 24 november 2005, Promotor : Wieringa, B. Co-promotores : Fransen, J.A.M., Hendriks, W.J.A.J., Item does not contain fulltext, Previous work has revealed the existence of two Protein Tyrosine Phosphatases in mouse, PTPBR7 and PTP-SL, that were in part identical, suggesting that they originated from the same gene, termed Ptprr (1,5,6). In this thesis, I report on the characterization of the various PTPRR isoforms in neuronal cells and demonstrate that the single copy mouse gene Ptprr gives rise to four mRNAs that encode PTPBR7, PTP-SL and two PTPPBS protein variants through the use of distinct promoters, alternative splicing and differential translation initiation starts. In addition, the receptor-type PTPBR7 protein isoform was found to undergo N-terminal proteolytic cleavage at a furin-like convertase consensus site, adding an additional, fifth, member for which the name PTPBR7-65 was coined. Localization studies that focused on the different PTPRR isoforms revealed that PTPBR7 and PTP-SL are both present and co-localize in late endocytic compartments and in the Golgi area. PTPBR7 shows an additional localization at the plasma membrane (1,7), and interestingly on early endosomes as well. The 42 and 37 kDa PTPPBS proteins are genuine cytosolic proteins. Live-imaging studies revealed that PTPBR7 and PTP-SL vesicles are highly motile in both anterograde and retrograde directions. PTP-SL is involved in the ERK-MAP kinase signaling pathway, but interestingly, we also found it to interact with the 4-adaptin subunit of the AP-4 adaptor complex, an important component of the vesicular transport machinery. Taken together, studies described in this thesis point to a possible role for PTP-SL, and other PTPRR family members, in vesicle trafficking between the Golgi-apparatus and endocytic compartments and localized signaling. more...
- Published
- 2005
48. Identification of a rat model for usher syndrome type 1B by N-ethyl-N-nitrosourea mutagenesis-driven forward genetics.
- Author
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Smits, B.M., Peters, T.A., Mul, J.D., Croes, H.J.E., Fransen, J.A.M., Beynon, A.J., Guryev, V., Plasterk, R.H., Cuppen, E.P.J.G., Smits, B.M., Peters, T.A., Mul, J.D., Croes, H.J.E., Fransen, J.A.M., Beynon, A.J., Guryev, V., Plasterk, R.H., and Cuppen, E.P.J.G. more...
- Abstract
Contains fulltext : 47555.pdf (publisher's version ) (Closed access), The rat is the most extensively studied model organism and is broadly used in biomedical research. Current rat disease models are selected from existing strains and their number is thereby limited by the degree of naturally occurring variation or spontaneous mutations. We have used ENU mutagenesis to increase genetic variation in laboratory rats and identified a recessive mutant, named tornado, showing aberrant circling behavior, hyperactivity, and stereotypic head shaking. More detailed analysis revealed profound deafness due to disorganization and degeneration of the organ of Corti that already manifests at the onset of hearing. We set up a single nucleotide polymorphism (SNP)-based mapping strategy to identify the affected gene, revealing strong linkage to the central region of chromosome 1. Candidate gene resequencing identified a point mutation that introduces a premature stopcodon in Myo7a. Mutations in human MYO7A result in Usher syndrome type 1B, a severe autosomal inherited recessive disease that involves deafness and vestibular dysfunction. Here, we present the first characterized rat model for this disease. In addition, we demonstrate proof of principle for the generation and cloning of human disease models in rat using ENU mutagenesis, providing good perspectives for systematic phenotypic screens in the rat. more...
- Published
- 2005
49. Microdomains of the C-type lectin DC-SIGN are portals for virus entry into dendritic cells.
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Cambi, A., Lange, F. de, Maarseveen, N.M. van, Nijhuis, M., Joosten, B.H.G.M., Dijk, E.M. van, Bakker, B.I. de, Fransen, J.A.M., Bovee-Geurts, P.H.M., Leeuwen, F.N. van, Hulst, N.F. van, Figdor, C.G., Cambi, A., Lange, F. de, Maarseveen, N.M. van, Nijhuis, M., Joosten, B.H.G.M., Dijk, E.M. van, Bakker, B.I. de, Fransen, J.A.M., Bovee-Geurts, P.H.M., Leeuwen, F.N. van, Hulst, N.F. van, and Figdor, C.G. more...
- Abstract
Item does not contain fulltext, The C-type lectin dendritic cell (DC)-specific intercellular adhesion molecule grabbing non-integrin (DC-SIGN; CD209) facilitates binding and internalization of several viruses, including HIV-1, on DCs, but the underlying mechanism for being such an efficient phagocytic pathogen-recognition receptor is poorly understood. By high resolution electron microscopy, we demonstrate a direct relation between DC-SIGN function as viral receptor and its microlocalization on the plasma membrane. During development of human monocyte-derived DCs, DC-SIGN becomes organized in well-defined microdomains, with an average diameter of 200 nm. Biochemical experiments and confocal microscopy indicate that DC-SIGN microdomains reside within lipid rafts. Finally, we show that the organization of DC-SIGN in microdomains on the plasma membrane is important for binding and internalization of virus particles, suggesting that these multimolecular assemblies of DC-SIGN act as a docking site for pathogens like HIV-1 to invade the host. more...
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- 2004
50. A role for the small GTPase Rab21 in the early endocytic pathway.
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Simpson, J.C., Griffiths, G.L., Wessling-Resnick, M., Fransen, J.A.M., Bennett, H., Jones, A.T., Simpson, J.C., Griffiths, G.L., Wessling-Resnick, M., Fransen, J.A.M., Bennett, H., and Jones, A.T.
- Abstract
Contains fulltext : 57485.pdf (publisher's version ) (Closed access), Rab proteins comprise a family of monomeric GTPases that control cellular membrane traffic. Rab21 is a poorly characterised member with no known function. Human Rab21 cDNA from K562 cells was subcloned into GFP expression vectors to generate Rab21 and Rab21 mutants defective in either GTP hydrolysis (Rab21 Q78L) or binding (Rab21 T33N) for transfection studies in HeLa cells. Confocal fluorescence microscopy and ultrastructural studies revealed Rab21 to be predominantly localised to the early endocytic pathway, on vesicles containing earlyendosomal antigen 1 EEA1, transferrin receptor and internalised ligands. EEA1 was localised to enlarged endosomes in Rab21 wild-type expressing cells but the GTP hydrolysis and GDP binding mutants had unique phenotypes labelling tubular reticular structures and the trans-Golgi network, respectively. Early endosome localisation for Rab21 was confirmed in a hepatoma cell line that allowed analysis of the subcellular distribution of the endogenous protein. Comparison of the localisation of Rab21 with other Rabs revealed extensive colocalisation with early endocytic variants Rab4, Rab5, Rab17 and Rab22 but much less overlap with those associated with late endosomes, recycling endosomes and the early secretory pathway. Cells expressing Rab21 T33N had defects in endocytosis of transferrin and epidermal growth factor and failed to effectively deliver the latter ligand to late endosomes and lysosomes for degradation. Collectively, our data provide the first characterisation of Rab21 function in early endosome dynamics. more...
- Published
- 2004
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