Mapping of a Conformational Epitope on Plasminogen Activator Inhibitor-1 by Random Mutagenesis

@article{Gorlatova2003MappingOA,
  title={Mapping of a Conformational Epitope on Plasminogen Activator Inhibitor-1 by Random Mutagenesis},
  author={N. Gorlatova and H. Elokdah and K. Fan and D. L. Crandall and D. Lawrence},
  journal={The Journal of Biological Chemistry},
  year={2003},
  volume={278},
  pages={16329 - 16335}
}
The mechanism for the conversion of plasminogen activator inhibitor-1 (PAI-1) from the active to the latent conformation is not well understood. Recently, a monoclonal antibody, 33B8, was described that rapidly converts PAI-1 to the latent conformation (Verhamme, I., Kvassman, J. O., Day, D., Debrock, S., Vleugels, N., Declerck, P. J., and Shore, J. D. (1999) J. Biol. Chem. 274, 17511–17517). In an attempt to understand this interaction, and more broadly to understand the mechanism of the… Expand
Elucidation of the epitope of a latency-inducing antibody: identification of a new molecular target for PAI-1 inhibition.
TLDR
The three dimensional localization of this epitope and its differential exposure in active and latent forms of PAI-1 provide a molecular explanation for the underlying mechanism of MA-33B8. Expand
Crystal Structure of Plasminogen Activator Inhibitor-1 in an Active Conformation with Normal Thermodynamic Stability*
TLDR
The crystal structure of PAI-1 W175F is reported as the first model of the metastable native molecule and the previously identified chloride-binding site close to the F-helix is absent from the present structure and likely to be artifactual, because of its dependence on the 14-1B mutations. Expand
Structural Differences between Active Forms of Plasminogen Activator Inhibitor Type 1 Revealed by Conformationally Sensitive Ligands*
TLDR
A model of the native conformation of wtPAI-1 is proposed, in which the bottom of the central sheet is closed, whereas the top of the β-sheet A is open to allow partial insertion of the RCL. Expand
Characterization of a Site on PAI-1 That Binds to Vitronectin Outside of the Somatomedin B Domain*
TLDR
It is hypothesized that, together, the two sites form an extended binding area that may promote assembly of higher order vitronectin-PAI-1 complexes. Expand
The reactive-center loop of active PAI-1 is folded close to the protein core and can be partially inserted.
TLDR
It is proposed that the close proximity of the RCL to the protein core, and the ability of the loop to preinsert into beta-sheet A is a possible reason for PAI-1 being able to convert spontaneously to its latent form. Expand
A Peptide Accelerating the Conversion of Plasminogen Activator Inhibitor-1 to an Inactive Latent State
TLDR
The results show that paionin-4 inactivates PAI-1 by a mechanism clearly different from other peptides, small organochemical compounds, or antibodies, whether they cause inactivation by stimulating latency transition or by other mechanisms, and that the loop between α-helix D and β-strand 2A can be a target for PAi-1 in activation by different types of compounds. Expand
Biochemical properties of plasminogen activator inhibitor-1.
TLDR
Studies of PAI-1 have contributed significantly to the elucidation of the protease inhibitory mechanism of serpins, which is based on a metastable native state becoming stabilised by insertion of the RCL into the central beta-sheet A and formation of covalent complexes with target proteases. Expand
Latency and Substrate Binding Globally Reduce Solvent Accessibility of Plasminogen Activator Inhibitor Type 1 (PAI-1)
TLDR
The results demonstrate that the most dynamic regions of PAI-1 (the RCL, helices D and A, and sheet 5A) are flexible in the transition toward latency and show that the dynamic surface structures of the active, latent, and peptide-annealed conformers of PAi-1 are underestimated by theoretical solvent accessibility calculations derived from crystallographic data. Expand
Evidence for a Pre-latent Form of the Serpin Plasminogen Activator Inhibitor-1 with a Detached β-Strand 1C*
TLDR
Evidence is provided for the existence of an equilibrium between active PAI-1 and a pre-latent form, characterized by reversible detachment of s1C and formation of a glycan-shielded cleft in the molecule. Expand
Mechanism of Inactivation of Plasminogen Activator Inhibitor-1 by a Small Molecule Inhibitor*
TLDR
It is suggested for the first time a novel pool of PAI-1 exists that is vulnerable to inhibition by inactivators that bind at the vitronectin binding site. Expand
...
1
2
3
4
...

References

SHOWING 1-10 OF 45 REFERENCES
Structural basis of latency in plasminogen activator inhibitor-1
TLDR
The structure of intact latent PAI-1 determined by single-crystal X-ray diffraction reveals that residues on the N-terminal side of the primary recognition site are inserted as a central strand of the largest βsheet, in positions similar to the corresponding residues in the cleaved form of the serpin α1proteinase inhibitor (α1-PI). Expand
The active conformation of plasminogen activator inhibitor 1, a target for drugs to control fibrinolysis and cell adhesion.
TLDR
The structure clarifies the molecular basis of the stabilizing mutations and the reduced affinity of PAI-1, on cleavage or in the latent form, for vitronectin and suggests a new mechanism for the serpin polymerization associated with certain diseases. Expand
Neutralization of plasminogen activator inhibitor-1 inhibitory properties: identification of two different mechanisms.
TLDR
Two distinct mechanisms by which the inhibitory activity of PAI-1 can be neutralized are demonstrated, which may have implications for the design of therapeutic or preventive strategies to interfere with PAi-1 activity. Expand
Accelerated Conversion of Human Plasminogen Activator Inhibitor-1 to Its Latent Form by Antibody Binding*
The serpin plasminogen activator inhibitor-1 (PAI-1) slowly converts to an inactive latent form by inserting a major part of its reactive center loop (RCL) into its β-sheet A. A murine monoclonalExpand
Molecular evolution of plasminogen activator inhibitor‐1 functional stability.
TLDR
The nature of the identified mutations implies that the unique instability of the PAI‐1 active conformation evolved through global changes in protein packing and suggest a selective advantage for transient inhibitor function. Expand
Kinetic characterization of the substrate reaction between a complex of antithrombin with a synthetic reactive-bond loop tetradecapeptide and four target proteinases of the inhibitor.
TLDR
Data show that blocking by the peptide of the putative intramolecular association of the P1 to P14 region of the AT reactive-bond loop with the A beta-sheet leads to AT functioning as a substrate of its target enzymes with an efficiency that equals or exceeds the action of uncomplexed AT as an inhibitor and with the expected heparin activation. Expand
Inhibitory mechanism of serpins: loop insertion forces acylation of plasminogen activator by plasminogen activator inhibitor-1.
TLDR
The ability of tPA to discriminate between the two PAI-1 forms to exosite bonds that cannot occur with trypsin is attributed, resulting in faster acylation than with substrate PAi-1. Expand
Structure-function studies of the SERPIN plasminogen activator inhibitor type 1. Analysis of chimeric strained loop mutants.
TLDR
Experiments suggest that the strained loop of PAI-1 is not responsible for the transition between the latent and the active conformations or for binding to vitronectin. Expand
Serpin reactive center loop mobility is required for inhibitor function but not for enzyme recognition.
TLDR
Results suggest that while insertion of the reactive center loop is not essential for protease binding, it is a necessary second step required for inhibitor function. Expand
The Acid Stabilization of Plasminogen Activator Inhibitor-1 Depends on Protonation of a Single Group That Affects Loop Insertion into β-Sheet A (*)
TLDR
It is found that peptide binding and formation of latent PAI-1 are mutually exclusive events, similarly affected by the pKa 7.6 ionization, which is direct evidence that external peptides can substitute for strand 4 in β-sheet A of PAi-1 and that the p Ka 7. Expand
...
1
2
3
4
5
...