). The following sequences were specifically targeted for human STUB1 cDNA: #1 (5′-AGGCCAAGCACGACAAGTA-3′); #2 (5′-GTGAGAGGGAGCTGGAAGA-3′); #3 (5′-CGCTGGTGGCCGTGTATTA-3′). To establish stable cell lines expressing RNAi, Jurkat E6 cells were transfected with RNAi plasmids by standard retroviral transduction procedures, and selected by puromycin. Total RNA was isolated from Jurkat E6 cells using RNAiso plus reagent (TAKARA) and cDNA was

IWR-1 in vitro synthesized using Superscript III cDNA synthesis kit (Invitrogen). Quantitative PCR reactions were performed on a CFX96 real-time system using the SybrGreen PCR Supermix according to manufacturer’s instructions (Bio-Rad). GAPDH was used as calibrators for normalization. Primer sequences are as following: GAPDH forward: 5′-GAGTCAACGGATTTGGTCGT-3′; GAPDH reverse: 5′-GACAAGCTTCCCGTTCTCAG-3′; IL-2 forward: 5′-GAACTCAAACCTCTGGAGGAAG-3′; Cabozantinib IL-2 reverse: 5′-GCTGTCTCATCAGCATATTCACAC-3′; STUB1 forward: 5′-TCAAGGAGCAGGGCAATCGTCT-3′; STUB1 reverse: 5′-GCATCTTCAGGTAGCACAAGGC-3′. IL-2 in culture medium was measured

using human IL-2 ELISA kit (BOSTER) according to the manufacturer’s instruction. We thank Prof. Youjia Cao (Nankai University, China) for providing Jurkat E6 cells. We thank Prof. Fuquan Yang, Mr. Peng Xue (Institute of Biophysics, Chinese Academy of Sciences), and Dr. Ying Li from our laboratory for technical help with mass spectrometry. This work was supported by grants from the National Natural Science Foundation of China (30700417, 30972719, 31170835, and 30921001 to Y. Liu enough and H. B. Shu). The authors declare

no financial or commercial conflict of interest. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Figure S1. Knockdown of STUB1 inhibits NF-κB activation and IL-2 transcription upon anti-CD3/CD28 stimulation. (A) Jurkat E6 cells (5 × 106) stably transfected with control RNAi or STUB1 RNAi were challenged with anti-CD3/CD28 Abs as indicated. Cell lysates were analyzed by immunoblotting with the indicated Abs (A). The experiments were repeated for three times with similar results. RNA was isolated and mRNA levels of indicated genes were investigated by quantitative real-time PCR (B). The graph show means ± SD, n = 3 (* p < 0.05). Figure S2. Knockdown of STUB1 inhibits the phosphorylation of IKK-α/β and TAK1 under P/I stimulation. Jurkat E6 cells (5 × 106) stably transfected with control RNAi or STUB1 RNAi were challenged with PMA/Ionomycin (P/I) (1 mMeach) as indicated. Cell lysates were analyzed by immunoblotting with the indicated Abs. Figure S3. Interaction between overexpressed STUB1 and pathway members involved in TCR signaling.