Regulation of plasmin activity by annexin II tetramer

Sandra L. Fitzpatrick, Geetha Kassam, Kyu Sil Choi, Hyoung Min Kang, Darin K. Fogg, David M. Waisman

Research output: Contribution to journalArticlepeer-review

43 Citations (Scopus)

Abstract

Annexin II tetramer (AIIt) is a major Ca2+-binding protein of the endothelial cell surface which has been shown to stimulate the tissue plasminogen activator (t-PA)-dependent conversion of plasminogen to plasmin. In the present report, we have examined the regulation of plasmin activity by AIIt. The incubation of plasmin with AIIt resulted in a 95% loss in plasmin activity. SDS-PAGE analysis established that AIIt stimulated the autoproteolytic digestion of plasmin heavy and light chains. The kinetics of AIIt-stimulated plasmin autoproteolysis were first-order, suggesting that binding of plasmin to AIIt resulted in the spontaneous autoproteolysis of the bound plasmin. AIIt did not affect the activity of other serine proteases such as t-PA or urokinase-type plasminogen activator. Furthermore, other annexins such as annexin I, II, V, or VI did not stimulate plasmin autoproteolysis. Increasing the concentration of AIIt on the surface of human 293 epithelial cells increased cell-mediated plasmin autoproteolysis. Thus, in addition to stimulating the formation of plasmin, AIIt also promotes plasmin inactivation. These results therefore suggest that AIIt may function to provide the cell surface with a transient pulse of plasmin activity.

Original languageEnglish
Pages (from-to)1021-1028
Number of pages8
JournalBiochemistry
Volume39
Issue number5
DOIs
Publication statusPublished - Feb 8 2000
Externally publishedYes

ASJC Scopus Subject Areas

  • Biochemistry

Fingerprint

Dive into the research topics of 'Regulation of plasmin activity by annexin II tetramer'. Together they form a unique fingerprint.

Cite this