PLG

Fig1. The plasminogen activator system. Tissue-type- and Urokinase- plasminogen activators (tPA and uPA) activate the inactive zymogen plasminogen (Plg) into active plasmin (Plm). (Anupriya Mehra, 2016)

What is PLG protein?

PLG (plasminogen) gene is a protein coding gene which situated on the long arm of chromosome 6 at locus 6q26. The protein encoded by this gene is a secreted blood zymogen that is activated by proteolysis and converted to plasmin (PLM) and angiostatin. PLM dissolves fibrin in blood clots and is an important protease in many other cellular processes while angiostatin inhibits angiogenesis. PLG is also named plasminogen kringles 1-4 and PK1-4. The PLG protein is consisted of 810 amino acids and its molecular mass is approximately 90.6 kDa.

What is the function of PLG protein?

PLG interacts with PLG receptors which results in the retention of plasmin on cell surfaces and in plasmin-induced cell signaling. The localization of PLG on cell surfaces plays a role in the degradation of extracellular matrices, cell migration, inflamation, wound healing, oncogenesis, metastasis, myogenesis, muscle regeneration, neurite outgrowth, and fibrinolysis. This protein may also play a role in acute respiratory distress syndrome (ARDS) which, in part, is caused by enhanced clot formation and the suppression of fibrinolysis.

Fig2. The broadening role of the plasminogen-activating system in physiology and pathophysiology. (Charithani B Keragala, 2021)

PLG Related Signaling Pathway

Plasminogen activation system: In the plasminogen activation system, PLG participates in the process of fibrinolysis by binding to its receptor, such as tissue-type plasminogen activator (tPA), and being activated by tPA as plasmin.

Plasminogen receptor signaling pathway: PLG can bind to plasminogen receptors (such as annexin A2) on the cell surface and participate in cell migration, proliferation and transformation by activating the signaling pathway on the receptor.

Fibrinogen interaction signaling pathway: In the process of platelet activation and thrombosis, the interaction between plasminogen and fibrinogen can regulate platelet aggregation and thrombosis formation through the participation of PLG.

PLG Related Diseases

Defects in this gene are likely a cause of thrombophilia and ligneous conjunctivitis. Diseases associated with PLG include plasminogen deficiency and angioedema. PLG plays an important role in fibrinolytic systems. Its abnormal function can lead to abnormal degradation of blood vessel walls and clotting factors, resulting in bleeding or hemostasis disorders. Or participate in the invasion and metastasis of tumor cells.

Bioapplications of PLG

Treatment of thrombotic diseases: PLG can be used to treat thrombotic diseases such as deep vein thrombosis and pulmonary embolism. By injecting PLG, it can promote the dissolution of thrombus and restore blood circulation. Anticoagulant therapy: PLG can be used as an anticoagulant therapy to prevent blood clotting. For example, PLG can be used for prophylactic anticoagulant therapy in heart surgery, vascular surgery and other surgeries that need to prevent thrombosis.

Case Study 1: Claire S Whyte, 2015

The interaction of plasminogen with platelets and their localization during thrombus formation and fibrinolysis under flow are not defined. Using a novel model of whole blood thrombi (Thrombi were perfused with 0.8 μM glu-plasminogen labeled with DyLight 633 (DL633)), formed under flow, the dose-dependent fibrinolysis using fluorescence microscopy was examined. The article indicates that different subpopulations of platelets harbor plasminogen by diverse mechanisms and provide an essential scaffold for the accumulation of fibrinolytic proteins that mediate fibrinolysis under flow.

Fig1. Plasminogen localization within thrombi.

Fig2. During tPA-mediated fibrinolysis, maximal plasminogen signal was visualized at t = 3 minutes, followed by a reduction in signal as the fibrin(ogen) was degraded.

PLG has several biochemical functions, for example, apolipoprotein binding,protein binding,protein domain specific binding. Some of the functions are cooperated with other proteins, some of the functions could acted by PLG itself. We selected most functions PLG had, and list some proteins which have the same functions with PLG. You can find most of the proteins on our site.

PLG has direct interactions with proteins and molecules. Those interactions were detected by several methods such as yeast two hybrid, co-IP, pull-down and so on. We selected proteins and molecules interacted with PLG here. Most of them are supplied by our site. Hope this information will be useful for your research of PLG.

q6v4l1_strpy;q6v4l4_strpy;q6v4l5_strpy;q6v4l9_strpy;sak;ATP2;ATP1;ATP15