PEN-2
PEN-2 ( presenilin enhancer 2 ) is a protein that is a regulatory component of the gamma secretase complex , a protease complex responsible for proteolysis of transmembrane proteins such as the Notch protein and amyloid precursor protein ( APP ) . 
<triplet> amyloid precursor protein <subj> protein <obj> instance of <subj> Notch protein <obj> biological process