SKP2 and hereditary sensory and autonomic neuropathy: However, calf intestinal alkaline phosphatase (CIP) treatment did not affect the binding of SFB-YAP (which was purified from HEK293T cells and was phosphorylated without CIP treatment) to purified MBP-SKP2 protein (Fig. 2e), suggesting that SKP2 binds YAP in a YAP phosphorylation-independent manner.