Arginase-flotillin interaction brings arginase to red blood cell membrane

Flotillin-1 and arginase are both up-regulated in red blood cell membrane of type 2 diabetic patients. For studying why the soluble arginase can bind to the membrane and whether such binding would modify arginase activity, the arginase1 and related proteins were cloned and expressed. The results showed that flotillin-1 can interact with arginase1, and hence arginase activity was up-regulated by 26.8%. It was estimated that about 61% of arginase1 is bound to the membrane mediated by flotillin-1. The arginase activity in diabetic patients was significantly higher than that of the controls (752.4+/-38.5 U/mg protein vs 486.7+/-28.7 U/mg protein).