Nuclear protein analysis was performed as previously described (44 (link)) using anti-Notch1val1744 (Cell Signaling Technology, 4147S), anti-Notch2 (Cell Signaling Technology, D76A6), anti-Notch3 (Cell Signaling Technology, D11B8), anti-Notch4 (Cell Signaling Technology, L5C5), anti-MAML1 (Cell Signaling Technology, D3K7B), anti-MAML2 (Cell Signaling Technology, D41E6), anti-MAML3 (Bethyl Laboratories, A300–6841), and anti-RBPSUH (CSL, Cell Signaling Technology, D104A).