Thrombin induces endothelial cell-surface exposure of the plasminogen receptor annexin 2

Peterson, Erica A.; Sutherland, Michael R.; Nesheim, Michael E.; Pryzdial, Edward L. G.

doi:10.1242/jcs.00434

Cited by 61 publications

(63 citation statements)

References 68 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We and others have shown previously that thrombin, the primary procoagulant protease, paradoxically limits fibrin deposition by triggering PAR1-mediated tyrosine 23 phosphorylation of A2, cell surface translocation of (A2⅐p11) 2 , and accelerated t-PAdependent plasmin generation (16,17). In the present study, we found that plasmin, the primary profibrinolytic protease, paradoxically limits its own activation by cleaving cell surface A2 and eliciting cPKC activation and serine phosphorylation of intracellular A2.…”

Section: A Either Anxa2supporting

confidence: 63%

See 1 more Smart Citation

Feedback Regulation of Endothelial Cell Surface Plasmin Generation by PKC-dependent Phosphorylation of Annexin A2

He¹,

Sui

Xiong

et al. 2011

Journal of Biological Chemistry

View full text Add to dashboard Cite

In response to blood vessel injury, hemostasis is initiated by platelet activation, advanced by thrombin generation, and tempered by fibrinolysis. The primary fibrinolytic protease, plasmin, can be activated either on a fibrin-containing thrombus or on cells. Annexin A2 (A2) heterotetramer (A2⅐p11) 2 is a key profibrinolytic complex that assembles plasminogen and tissue plasminogen activator and promotes plasmin generation. We now report that, in endothelial cells, plasmin specifically induces activation of conventional PKC, which phosphorylates serine 11 and serine 25 of A2, triggering dissociation of the (A2⅐p11) 2 tetramer. The resulting free p11 undergoes ubiquitinmediated proteasomal degradation, thus preventing further translocation of A2 to the cell surface. In vivo, pretreatment of A2 ؉/؉ but not A2 ؊/؊ mice with a conventional PKC inhibitor significantly reduced thrombosis in a carotid artery injury model. These results indicate that augmentation of fibrinolytic vascular surveillance by blockade of serine phosphorylation is A2-dependent. We also demonstrate that plasmin-induced phosphorylation of A2 requires both cleavage of A2 and activation of Toll-like receptor 4 on the cell surface. We propose that plasmin can limit its own generation by triggering a finely tuned "feedback" mechanism whereby A2 becomes serine-phosphorylated, dissociates from p11, and fails to translocate to the cell surface.The human hemostatic system represents a coordinated balance between procoagulant and anticoagulant/profibrinolytic activities. Together, these systems prevent blood loss while maintaining blood flow. Plasmin, the major protease of the fibrinolytic system, acts to digest insoluble fibrin into soluble fibrin degradation products. Plasmin generation is modulated by plasminogen activators and plasminogen activator inhibitors and is further regulated by binding of plasminogen and its activators to cell surface receptors (1). Membrane-associated annexin A2 (A2) 3 is part of a heterotetrameric complex in which the N termini of two copies of A2 bind to two copies of the S100 family protein, S100A10 (p11) (2). A2, a member of the annexin superfamily, consists of a highly conserved C-terminal phospholipid-binding core domain and an N-terminal ligandinteracting domain (3). Complex formation with p11 increases the affinity of A2 for calcium and phospholipids, thereby directing it to cellular membranes (4). Components of the (A2⅐p11) 2 tetramer, moreover, specifically bind tissue plasminogen activator (t-PA) and plasminogen and strongly enhance plasmin generation (5-8, 52).Several lines of evidence identify the (A2⅐p11) 2 complex as a significant regulator of fibrin balance in vivo. First, A2 Ϫ/Ϫ microvascular endothelial cells lack t-PA cofactor activity, and the fibrin content of highly perfused A2 Ϫ/Ϫ tissues is ϳ2-fold greater than that observed in wild type controls (9). In addition, arterial injury in A2 Ϫ/Ϫ mice is followed by a 2-fold increase in thrombotic vascular occlusion with an equivalent reduction in blood flo...

show abstract

Section: A Either Anxa2supporting

confidence: 63%

“…It is clear that translocation of the (A2⅐p11) 2 complex to the cell surface is initiated by signals, such as heat stress and thrombin exposure, which activate a Src-like kinase that phosphorylates A2 at tyrosine 23 (16,17). It is also known that trafficking of A2 to the cell surface requires the presence of p11 (16).…”

mentioning

confidence: 99%

Feedback Regulation of Endothelial Cell Surface Plasmin Generation by PKC-dependent Phosphorylation of Annexin A2

He¹,

Sui

Xiong

et al. 2011

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…ABCA-1 levels in PC3 and LNCaP was determined using Western blots from total lysate (E). is externalized to the outer leaflet of the plasma membrane accompanied by associated proteins (38). Intriguingly, HSP70 has been shown to bind phosphatidylserine, although the significance of this interaction for HSP70 release has not been determined (39).…”

Section: Discussionmentioning

confidence: 99%

Heat Shock Protein 70 Is Secreted from Tumor Cells by a Nonclassical Pathway Involving Lysosomal Endosomes

Mambula

Calderwood

2006

The Journal of Immunology

307

265

View full text Add to dashboard Cite

Heat shock protein (HSP)70 can be released from tumor cells and stimulate a potent antitumor immune response. However, HSP70 does not contain a consensus secretory signal and thus cannot traverse the plasma membrane by conventional mechanisms. We have observed HSP70 release from intact human prostate carcinoma cell lines (PC-3 and LNCaP) by a mechanism independent of de novo HSP70 synthesis or cell death. This pathway is similar to one used by the leaderless protein IL-1β. Our studies show that HSP70 release involves transit though an endolysosomal compartment and is inhibited by lysosomotropic compounds. In addition, the rate of HSP70 secretion correlates well with the appearance of the lysosomal marker LAMP1 on the cell surface, further suggesting the role for endolysosomes. The entry of HSP70 into this secretory compartment appears to involve the ABC family transporter proteins and ABC transporter inhibitor glibenclamide antagonizes secretion. Although the cell signals involved in triggering stress induced HSP70 release though this lysosomal pathway are largely unknown, our experiments suggest a regulatory role for extracellular ATP. These mechanisms appear to be shared by IL-1β secretion. Following release, we observed the binding of extracellular HSP70 to the cell surface of the prostate carcinoma cells. These findings suggest that secreted HSP70 can take part in paracrine or autocrine interactions with adjacent cell surfaces. Our experiments therefore suggest a mechanism for HSP70 secretion and binding to the surface of other cells that may be involved in recognition of the tumor cells by the immune system.

show abstract

“…In this report, the EDTA washes are referred to as EDTA eluates. Cell-surface proteins were subjected to biotinylation with 0.5 mg/ml of EZ-link-sulfo-NHS biotin (Pierce) and recovered with avidin-conjugated Sepharose (Sigma), as previously described (Peterson et al, 2003).…”

Section: Edta Elution and Cell-surface Biotinylationmentioning

confidence: 99%

A competitive hexapeptide inhibitor of annexin A2 prevents hypoxia-induced angiogenic events

Valapala

Thamake

Vishwanatha

2011

Journal of Cell Science

View full text Add to dashboard Cite

SummaryExtracellular proteolysis is an indispensable requirement for the formation of new blood vessels during neovascularization and is implicated in the generation of several angiogenic regulatory molecules. Anti-proteolytic agents have become attractive therapeutic strategies in diseases associated with excessive neovascularization. Annexin A2 (AnxA2) is an endothelial cell-surface receptor for the generation of active proteolytic factors, such as plasmin. Here, we show that AnxA2 is abundantly expressed in the neovascular tufts in a murine model of neovascularization. Exposure to hypoxic conditions results in elevation of AnxA2 and tissue plasminogen activator (tPA) in human retinal microvascular endothelial cells (RMVECs). We show that the hexapeptide competitive inhibitor LCKLSL, which targets the N-terminal tPA-binding site of AnxA2, binds efficiently to cell-surface AnxA2 compared with binding of the control peptide LGKLSL. Treatment with the competitive peptide inhibits the generation of plasmin and suppresses the VEGFinduced activity of tPA under hypoxic conditions. Application of the competitive peptide in two in vivo models of angiogenesis demonstrated suppression of the angiogenic responses, which was also associated with significant changes in the vascular sprouting. These results suggest that AnxA2-mediated plasmin generation is an important event in angiogenesis and is inhibited by a specific competitive peptide that inhibits the binding of tPA to AnxA2.

show abstract

Thrombin induces endothelial cell-surface exposure of the plasminogen receptor annexin 2

Cited by 61 publications

References 68 publications

Feedback Regulation of Endothelial Cell Surface Plasmin Generation by PKC-dependent Phosphorylation of Annexin A2

Feedback Regulation of Endothelial Cell Surface Plasmin Generation by PKC-dependent Phosphorylation of Annexin A2

Heat Shock Protein 70 Is Secreted from Tumor Cells by a Nonclassical Pathway Involving Lysosomal Endosomes

A competitive hexapeptide inhibitor of annexin A2 prevents hypoxia-induced angiogenic events

Contact Info

Product

Resources

About