Functions together with PI31 to control non-apoptotic caspase activation during sperm individualization. Positively regulates PI31 stability. Component of an SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complex, at least composed of ntc, skpA and Cul1. Interacts (via F-box domain) with skpA and Cul1. Interacts with Prosalpha7 and PI31. Interacts with Bruce. In the spermatid, colocalizes with Cul1 at the actin-based individualization complex and the cystic bulge. Expressed in testis (at protein level). Male sterility.