Loss of Rnase1 Produces Coagulation Abnormalities in Mice

Ribonuclease 1 (RNase 1) is a secreted enzyme with robust and nonspecific endoribonucleolytic activity. It is present in all vertebrate species and is expressed ubiquitously in human tissue, but its biological function is not well understood. In recent years, however, clues to its activity have emerged. RNase 1 is most highly produced in vascular endothelial cells and has a pH optimum of 7.2, which suggests that its main activity is in the blood. Additionally, multiple publications have highlighted the ability of a homolog of RNase 1 (the more famous Ribonuclease A) to prevent or reduce RNA‐mediated thrombosis when administered to mice. These findings suggest a role for endogenous RNase 1 in modulation of the coagulation cascade, and we are evaluating this hypothesis in an Rnase1 knockout mouse system.