• Login as Editor
    View Item 
    •   Yeshiva Academic Institutional Repository
    • Albert Einstein College of Medicine (AECOM)
    • Albert Einstein College of Medicine: Doctoral Dissertations
    • View Item
    •   Yeshiva Academic Institutional Repository
    • Albert Einstein College of Medicine (AECOM)
    • Albert Einstein College of Medicine: Doctoral Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Endothelial cell acidic fibroblast growth factor binding proteins

    Thumbnail
    Date
    1994
    Author
    Samathanam, Christina Ann
    Metadata
    Show full item record
    Abstract
    This thesis has focused on endothelial cell proteins which interact with fibroblast growth factor-1 (FGF-1). Endothelial cell extracellular matrix (ECM) heparan sulfate proteoglycans (HSPGs) which interact with FGF-1 play an important role in controlling cell growth. We have investigated the ability of ECM HSPG{dollar}\sp{lcub}\rm P{rcub}{dollar} (potentiator) isolated from different passages to augment the FGF-1 mitogenic activity. HUVEC was demonstrated to produce ECM HSPGs that are potent endothelial cell growth potentiator (HSPG{dollar}\sp{lcub}\rm P{rcub}{dollar}) and inhibitor (HSPG{dollar}\sp{lcub}\rm I{rcub}{dollar}). HSPG{dollar}\sp{lcub}\rm P{rcub}{dollar} extracted from the ECM of cultured endothelial cells bind FGF-1 and potentiate the mitogenic activity of FGF-1. Deposition of HSPG{dollar}\sp{lcub}\rm P{rcub}{dollar} in the ECM was induced by heparin and FGF-1. The late passaged endothelial cells produce decreased amounts of ECM HSPG{dollar}\sp{lcub}\rm P{rcub}{dollar}. In addition, the HSPG{dollar}\sp{lcub}\rm P{rcub}{dollar} from late passaged cells were less sulfated and exhibited a decreased ability to augment FGF-1 mitogenic activity. The ECM HSPG{dollar}\sp{lcub}\rm P{rcub}{dollar} from late passaged cells gradually lost the ability to augment FGF-1 mitogenic activity.;In an attempt to understand the nuclear events associated with FGF-1 the cytosolic and nuclear proteins of HUVEC which interact with FGF-1 were isolated and identified.;We identified four (68, 78, 90 and 120kD) cytosolic proteins which interact with FGF-1. Partial N-terminal amino acid sequence of the 68kD protein demonstrated that it was related to human calreticulin, a calcium binding protein. In addition, recombinant skeletal muscle calreticulin, a calcium binding protein, was found not to bind a mutant FGF-1 in which the NLS sequence (-NYKKPKL-) was deleted. Also calreticulin was shown to enhance the accumulation of FGF-1, NLS peptide, and SV 40 large T antigen NLS peptide fluorescent conjugate in the nuclei of digitonin permeabilized HUVEC and NRK 52E cells.;We isolated two nuclear proteins, one 52kD and the other 63kD, which interact with FGF-1. The 63kD protein, which was isolated utilizing HSPG{dollar}\sp{lcub}\rm P{rcub}{dollar}-chromatography, interacted with a peptide containing the putative FGF-1 NLS sequence (CGGGNYKKPKL) and to a lesser degree to a synthesized NLS mutant (CGGGNYTKPKL). In an in vitro nuclear binding assay, saturable binding of {dollar}\sp{lcub}125{rcub}{dollar}I-HSA-NLS and {dollar}\sp{lcub}125{rcub}{dollar}I-FGF-1 was demonstrated. Less binding of {dollar}\sp{lcub}125{rcub}{dollar}I-HSA-NLS mutant and {dollar}\sp{lcub}125{rcub}{dollar}I-FGF-1U (mutant, NLS-NYKKPKL-deleted) to isolated HUVEC nuclei was observed. The p63 HUVEC nuclear envelope protein inhibited nuclear binding of both the {dollar}\sp{lcub}125{rcub}{dollar}I-HSA-NLS and {dollar}\sp{lcub}125{rcub}{dollar}I-FGF-1 to isolated nuclei. Using an in vitro nuclear import assay the import of FGF-1 and fluorescent conjugates of the NLS peptides into the nucleus, were found to require ATP and to be temperature dependent. Also, the NLS of FGF-1 was required for binding and translocation of FGF-1 into the nucleus. In addition the 63kD nuclear envelope protein inhibited the import of FGF-1 into the nucleus. The 52kD protein on the other hand was identified to be related to calreticulin, based on the partial N-terminal amino acid sequence. Thus we have identified and partially characterized endothelial cell proteins which interact with FGF-1 and modulate nuclear binding and transport of FGF-1 into the nucleus. (Abstract shortened by UMI.).
    Permanent Link(s)
    https://yulib002.mc.yu.edu/login?url=http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqm&rft_dat=xri:pqdiss:9522504
    https://hdl.handle.net/20.500.12202/3589
    Collections
    • Albert Einstein College of Medicine: Doctoral Dissertations [1674]

    Yeshiva University Libraries copyright © 2021  DuraSpace
    YAIR Self-Deposit | YAIR User's Guide | Take Down Policy | Contact Us
    Yeshiva University
     

     

    Browse

    AllCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    Login as Editor

    Statistics

    View Usage Statistics

    Yeshiva University Libraries copyright © 2021  DuraSpace
    YAIR Self-Deposit | YAIR User's Guide | Take Down Policy | Contact Us
    Yeshiva University