LAUSR

We read with great interest the article on allostery in a protease from the blood coagulation cascade by Beeler et al.(1) in a recent issue of Journal of Thrombosis and Haemostasis. Herein, the authors conclude that the allosteric activation of coagulation factor VIIa (FVIIa) by tissue factor (TF) in lamprey (l-) appears indistinguishable from, and conserved compared to, that in human (h-); meaning that l-FVIIa is assumed to be catalytically incompetent unless allosterically activated by l-TF. The lamprey, an ancient jawless eel-like vertebrate, is a fascinating creature and studying its coagulation system can certainly lead to insights into molecular mechanisms of coagulation as well as evolutionary adaptations over hundreds of millions of years (reviewed in (2)). This article is protected by copyright. All rights reserved.