[Novel adaptor protein, STAP-2 functions as a signal modulator in immune system].
Signal-transducing adaptor protein-2 (STAP-2) was recently identified as a novel adaptor protein and is a family of STAP adaptor protein and has a variety of functions in cellular signal transductions. Especially STAP-2 has a crucial role in immune systems by controlling cytokine signal transduction. STAP-2 functionally interacts with STAT3 through its YXXQ motif and enhances STAT3 transcriptional activation. In contrast, STAP-2 interacts with STAT5 through its PH and SH2-like domains and decreases STAT5 activity. Importantly, STAP-2 also binds to MyD88 and IKK-alpha/beta and regulates LPS/TLR4 signaling. Moreover, STAP-2 interacts with Epstein-Barr virus-derived LMP1 and modulates LMP1-mediated NF-kappaB signaling. More importantly, experiments using STAP-2 deficient mice showed that STAP-2 modulated several T-cell functions. T-cells from STAP-2 deficient mice showed enhanced integrin-mediated cell adhesion to fibronectin. Furthermore STAP-2-deficient T-cells show reduced chemotaxis toward SDF-1alpha. These accumulated evidences indicate that novel adaptor protein STAP-2 plays an important modulator role in both of innate and adaptive immune systems.
Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University. you-1@pharm.hokudai.ac.jp
Yuichi
Y
Sekine
D048868:Adaptor Proteins, Signal Transducing / Q000502:physiology*; D000818:Animals; D016207:Cytokines / Q000502:physiology; D006801:Humans; D007107:Immune System; D051379:Mice; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000276:immunology; D051193:Toll-Like Receptors / Q000502:physiology
D048868:Adaptor Proteins, Signal Transducing; D016207:Cytokines; C523144:STAP2 protein, mouse; D051193:Toll-Like Receptors