scholarly journals Identification of a flexible loop region (297–313) of urokinase-type plasminogen activator, which helps determine its catalytic activity.

1998 ◽  
Vol 273 (8) ◽  
pp. 4810
Author(s):  
Ziyong Sun ◽  
Yongping Jiang ◽  
Zhong Ma ◽  
Hui Wu ◽  
Bei-Fang Liu ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Plasminogen Activator ◽  
Flexible Loop ◽  
Loop Region ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator

scholarly journals Constriction of carotid arteries by urokinase-type plasminogen activator requires catalytic activity and is independent of NH2-terminal domains

2009 ◽  
Vol 102 (11) ◽  
pp. 983-992 ◽  
Author(s):  
Philip Massey ◽  
Shinji Tanaka ◽  
Joshua Buckler ◽  
Bo Jiang ◽  
Anton McCourtie ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Plasminogen Activator ◽  
Carotid Arteries ◽  
Artery Wall ◽  
Kringle Domains ◽  
Type Plasminogen Activator ◽  
Endothelial Surface ◽  
Urokinase Type Plasminogen Activator ◽  
Human Arteries

SummaryUrokinase-type plasminogen activator (uPA) is expressed at increased levels in stenotic, atherosclerotic human arteries. However, the biological roles of uPA in the artery wall are poorly understood. Previous studies associate uPA with both acute vasoconstriction and chronic vascular remodeling and attribute uPA-mediated vasoconstriction to the kringle – not the catalytic domain of uPA. We used an in-vivo uPA overexpression model to test the hypothesis that uPA-induced vasoconstriction is a reversible vasomotor process that can be prevented – and uPA fibrinolytic activity preserved – by: 1) removing the growth factor and kringle domains; or 2) anchoring uPA to the endothelial surface. To test this hypothesis we constructed adenoviral vectors that express: wild-type rabbit uPA (AduPA); a uPA mutant lacking the NH2-terminal growth-factor and kringle domains (Adu-PAdel); a mutant lacking catalytic activity (AduPAS→A), and a cell-surface anchored mutant (AdTMuPA). uPA mutants were expressed and characterised in vitro and in carotid arteries in vivo. uPAS→A had no plasminogen activator activity. Activity was similar for uPA and uPAdel, whereas AdTMuPA had only cell-associated activity. AduPAS→A arteries were not constricted. AduPA, AduPAdel, and AdTM-uPA arteries were constricted (approximately 30% smaller lumens; p≤0.008 vs. AdNull arteries). Papaverine reversed constriction of AduPA arteries. uPA-mediated arterial constriction is a vasomotor process that is mediated by uPA catalytic activity, not by the NH2-terminal domains. Anchoring uPA to the endothelial surface does not prevent vasoconstriction. uPA catalytic activity, generated by artery wall cells, may contribute to lumen loss in human arteries. Elimination of uPA vasoconstrictor activity requires concomitant loss of fibrinolytic activity.

Nonproteolytic Induction of Catalytic Activity into the Single-Chain Form of Urokinase-Type Plasminogen Activator by Dipeptides

Biochemistry ◽  
2009 ◽  
Vol 48 (40) ◽  
pp. 9606-9617 ◽  
Author(s):  
Kenneth A. Bøtkjær ◽  
Aleksandra A. Byszuk ◽  
Lisbeth M. Andersen ◽  
Anni Christensen ◽  
Peter A. Andreasen ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Plasminogen Activator ◽  
Single Chain ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator ◽  
Chain Form

Urokinase type plasminogen activator and inhibitor type-1 plasma levels in colorectal cancer

2001 ◽  
Vol 120 (5) ◽  
pp. A599-A600 ◽  
Author(s):  
L HERSZENYI ◽  
F FARINATI ◽  
G ISTVAN ◽  
M PAOLI ◽  
G ROVERONI ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Plasminogen Activator ◽  
Plasma Levels ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator ◽  
Inhibitor Type

Expression and Characterization of Clustered Charge-to-Alanine Mutants of Low Mr Single-Chain Urokinase-Type Plasminogen Activator

1994 ◽  
Vol 71 (01) ◽  
pp. 134-140 ◽  
Author(s):  
S Ueshima ◽  
P Holvoet ◽  
H R Lijnen ◽  
L Nelles ◽  
V Seghers ◽  
...  
Keyword(s):  
Plasminogen Activator ◽  
Solvent Accessibility ◽  
Site Directed Mutagenesis ◽  
Clot Lysis ◽  
Wild Type ◽  
Single Chain ◽  
Charged Amino Acids ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator ◽  
Pharmacokinetic Properties

SummaryIn an effort to modify the fibrinolytic and/or pharmacokinetic properties of recombinant low M r single-chain urokinase-type plasminogen activator (rscu-PA-32k), mutants were prepared by site-directed mutagenesis of clusters of charged amino acids with the highest solvent accessibility. The following mutants of rscu-PA-32k were prepared: LUK-2 (Lys 212, Glu 213 and Asp 214 to Ala), LUK-3 (Lys 243 and Asp 244 to Ala), LUK-4 (Arg 262, Lys 264, Glu 265 and Arg 267 to Ala), LUK-5 (Lys 300, Glu 301 and Asp 305 to Ala) and LUK-6 (Arg 400, Lys 404, Glu 405 and Glu 406 to Ala).The rscu-PA 32k moictic3 were expressed in High Five Ttichoplasiani cells, and purified to humugciicily from the conditioned cell culture medium, with recoveries of 0.8 to 3.7 mg/1. The specific fibrinolytic activities (220,000 to 300,000 IU/mg), the rates of plasminogen activation by the single-chain moieties and the rates of conversion In lwo chain moieties by plasmin were comparable for mutant and wild-type rscu PA 32k moieties, with the exception of LUK-5 which was virtually inactive. Equi-effective lysis (50% in 2 h) of 60 pi 125I-fibrin labeled plasma clots submerged in 0.5 ml normal human plasma was obtained with 0.7 to 0.8 μg/ml of wild-type or mutant rscu-PA-3?.k, except with LUK-5 (no significant lysis with 16 pg/ml). Following bolus injection in hamsters, all rscu-PA-32k moieties had a comparably rapid plasma clearance (1.3 to 2.7 ml/min), as a result of a short initial half-life (1.4 to 2.5 min). In hamsters with pulmonary embolism, continuous intravenous infusion over 60 min at a dose of 1 mg/kg, resulted in 53 to 72% clot lysis with the mutants, but only 23% with LUK-5, as compared to 36% for wild-type rscu-PA-32k.These data indicate that clustered charge-to-alanine mutants of rscu-PA-32k, designed to eliminate charged regions with the highest solvent accessibility, do not have significantly improved functional, fibrinolytic or pharmacokinetic properties.

Inhibition in Purified Systems and in Human Plasma of Chimaeric Plasminogen Activators Consisting of the NH2-Terminal Region of Tissue-Type Plasminogen Activator and the COOH-Terminal Region of UrokinaseType Plasminogen Activator

1988 ◽  
Vol 60 (02) ◽  
pp. 247-250 ◽  
Author(s):  
H R Lijnen ◽  
L Nelles ◽  
B Van Hoef ◽  
F De Cock ◽  
D Collen
Keyword(s):  
Plasminogen Activator ◽  
Rate Constants ◽  
Plasminogen Activators ◽  
Second Order ◽  
Tissue Type ◽  
Single Chain ◽  
Chain Molecules ◽  
Order Rate ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator

SummaryRecombinant chimaeric molecules between tissue-type plasminogen activator (t-PA) and single chain urokinase-type plasminogen activator (scu-PA) or two chain urokinase-type plasminogen activator (tcu-PA) have intact enzymatic properties of scu-PA or tcu-PA towards natural and synthetic substrates (Nelles et al., J Biol Chem 1987; 262: 10855-10862). In the present study, we have compared the reactivity with inhibitors of both the single chain and two chain variants of recombinant u-PA and two recombinant chimaeric molecules between t-PA and scu-PA (t-PA/u-PA-s: amino acids 1-263 of t-PA and 144-411 of u-PA; t-PA/u-PA-e: amino acids 1-274 of t-PA and 138-411 of u-PA). Incubation with human plasma in the absence of a fibrin clot for 3 h at 37° C at equipotent concentrations (50% clot lysis in 2 h), resulted in significant fibrinogen breakdown (to about 40% of the normal value) for all two chain molecules, but not for their single chain counterparts. Preincubation of the plasminogen activators with plasma for 3 h at 37° C, resulted in complete inhibition of the fibrinolytic potency of the two chain molecules but did not alter the potency of the single chain molecules. Inhibition of the two chain molecules occurred with a t½ of approximately 45 min. The two chain variants were inhibited by the synthetic urokinase inhibitor Glu-Gly-Arg-CH2CCl with apparent second-order rate constants of 8,000-10,000 M−1s−1, by purified α2-antiplasmin with second-order rate constants of about 300 M−1s−1, and by plasminogen activator inhibitor-1 (PAI-1) with second-order rate constants of approximately 2 × 107 M−1s−1.It is concluded that the reactivity of single chain and two chain forms of t-PA/u-PA chimaers with inhibitors is very similar to that of the single and two chain forms of intact u-PA.

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