PMID- 9367352
OWN - NLM
STAT- MEDLINE
DCOM- 19971205
LR  - 20190516
IS  - 0892-6638 (Print)
IS  - 0892-6638 (Linking)
VI  - 11
IP  - 13
DP  - 1997 Nov
TI  - The amino-terminal fragment of human urokinase directs a recombinant chimeric 
      toxin to target cells: internalization is toxin mediated.
PG  - 1169-76
AB  - In contrast to two-chain urokinase (uPA), a chemical conjugate between uPA and 
      native saporin (a cytotoxic plant seed ribosome-inactivating protein) did not 
      require plasminogen activator inhibitors to be internalized. To dissect this 
      pathway, we constructed a chimera consisting of the amino-terminal fragment (ATF) 
      of human urokinase fused to a saporin isoform (SAP-3). The chimeric ATF-SAP toxin 
      was expressed in Escherichia coli, purified, and characterized for its 
      ribosome-inactivating activity. Besides being a potent inhibitor of protein 
      synthesis in cell-free assays, ATF-SAP was specifically cytotoxic toward cells 
      expressing human uPAR. Competition experiments indicated that both the human uPAR 
      and the LDL-related receptor protein are involved in mediating the cell killing 
      ability of ATF-SAP. We conclude that neither plasminogen activator inhibitors nor 
      the catalytic moiety of urokinase are necessary to initiate these internalization 
      pathways. Thus, saporin may play a role similar to plasminogen activator 
      inhibitors in its ability to trigger internalization of uPAR-bound ligands 
      through endocytic receptors.
FAU - Fabbrini, M S
AU  - Fabbrini MS
AD  - Dibit-Department of Biological and Technological Research, San Raffaele 
      Scientific Institute, Milano, Italy. fabbris@dibit.hsr.it
FAU - Carpani, D
AU  - Carpani D
FAU - Bello-Rivero, I
AU  - Bello-Rivero I
FAU - Soria, M R
AU  - Soria MR
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - FASEB J
JT  - FASEB journal : official publication of the Federation of American Societies for 
      Experimental Biology
JID - 8804484
RN  - 0 (Immunotoxins)
RN  - 0 (PLAUR protein, human)
RN  - 0 (Peptide Fragments)
RN  - 0 (Plant Proteins)
RN  - 0 (Protein Synthesis Inhibitors)
RN  - 0 (Receptors, Cell Surface)
RN  - 0 (Receptors, Urokinase Plasminogen Activator)
RN  - 0 (Recombinant Fusion Proteins)
RN  - 0 (Recombinant Proteins)
RN  - 0 (Ribosome Inactivating Proteins, Type 1)
RN  - 0 (urokinase-ATF-SAP-3, recombinant)
RN  - EC 3.2.2.- (N-Glycosyl Hydrolases)
RN  - EC 3.2.2.22 (Saporins)
RN  - EC 3.4.21.73 (Urokinase-Type Plasminogen Activator)
SB  - IM
MH  - Cell Line
MH  - Cell Survival/drug effects
MH  - Cloning, Molecular
MH  - Escherichia coli
MH  - Humans
MH  - Immunotoxins/*pharmacokinetics/toxicity
MH  - *N-Glycosyl Hydrolases
MH  - Peptide Fragments/*pharmacokinetics/toxicity
MH  - Plant Proteins/*pharmacokinetics/toxicity
MH  - Protein Synthesis Inhibitors/pharmacokinetics/toxicity
MH  - Receptors, Cell Surface/biosynthesis/physiology
MH  - Receptors, Urokinase Plasminogen Activator
MH  - *Recombinant Fusion Proteins
MH  - Recombinant Proteins/pharmacokinetics
MH  - Ribosome Inactivating Proteins, Type 1
MH  - Ribosomes/drug effects
MH  - Saporins
MH  - Tumor Cells, Cultured
MH  - Urokinase-Type Plasminogen Activator/*pharmacokinetics
EDAT- 1997/11/21 00:00
MHDA- 1997/11/21 00:01
CRDT- 1997/11/21 00:00
PHST- 1997/11/21 00:00 [pubmed]
PHST- 1997/11/21 00:01 [medline]
PHST- 1997/11/21 00:00 [entrez]
AID - 10.1096/fasebj.11.13.9367352 [doi]
PST - ppublish
SO  - FASEB J. 1997 Nov;11(13):1169-76. doi: 10.1096/fasebj.11.13.9367352.