Identification of poly(rC) binding protein 2 (PCBP2) as a target protein of immunosuppressive agent 15-deoxyspergualin.
15-Deoxyspergualin (DSG) is an immunosuppressive agent being clinically used. Unlike tacrolimus and cyclosporine A, it does not inhibit the calcineurin pathway, and its mechanism of action and target molecule have not been elucidated. Therefore, we previously prepared biotinylated derivative of DSG (BDSG) to fish up the target protein. In the present research, we identified poly(rC) binding protein 2 (PCBP2) as a DSG-binding protein using this probe. DSG was confirmed to bind to PCBP2 by pull-down assay. Intracellular localization of PCBP2 was changed from the nucleus to the cytoplasm by DSG treatment. DSG inhibited the cell growth, and over-expression of PCBP2 reduced the anti-proliferative activity of DSG. PCBP2 is known to regulate various proteins including STAT1/2. Thus, we found PCBP2 as the first target protein of DSG that can explain the immunosuppressive activity.
Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
Masataka
M
Murahashi
Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
Siro
S
Simizu
Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
Masahiko
M
Morioka
Department of Molecular Target Medicine, Aichi Medical University School of Medicine, 1-1 Yazako-Karimata, Nagakute 480-1195, Japan. Electronic address: umezawa@aichi-med-u.ac.jp.
Kazuo
K
Umezawa
D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D001665:Binding Sites; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D006146:Guanidines / Q000493:pharmacokinetics / Q000494:pharmacology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D011485:Protein Binding; D016601:RNA-Binding Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism
D006146:Guanidines; D007166:Immunosuppressive Agents; C501903:PCBP2 protein, human; D016601:RNA-Binding Proteins; D011994:Recombinant Proteins; C037258:gusperimus
15-Deoxyspergualin; Biotin conjugate; Poly(rC) binding protein 2 (PCBP2); Signal transducer and activator of transcription (STAT); Target protein