Favre H, Benhamou A, Finidori J, Kelly P A, Edery M
INSERM Unité 344-Endocrinologie Moléculaire, Institut National de la Santé et de la Recherche Médicale, Faculté de Médecine Necker-Enfants Malades, Paris, France.
FEBS Lett. 1999 Jun 18;453(1-2):63-6. doi: 10.1016/s0014-5793(99)00681-x.
A family of suppressors of cytokine signaling (SOCS) has recently been identified of which two members have been shown to block growth hormone (GH) signaling. Dose-response experiments were conducted in 293 cells and SOCS-1 and SOCS-3 were shown to inhibit the transcriptional activation of a GH-responsive element and suppressed Jak2 tyrosine kinase activity. SOCS-2 had two opposite effects: at low concentrations it inhibited GH-induced STAT5-dependent gene transcription, but restoration of GH signaling was observed at higher concentrations. In cotransfection studies, SOCS-2 was able to block the inhibitory effect of SOCS-1 but not that of SOCS-3 on GH signaling. These findings suggest that a major function for SOCS-2 is to restore the sensitivity to GH by overcoming the initial inhibitory effects of other endogenous SOCS molecules.
最近发现了一个细胞因子信号转导抑制因子（SOCS）家族，其中两个成员已被证明可阻断生长激素（GH）信号传导。在293细胞中进行了剂量反应实验，结果显示SOCS-1和SOCS-3可抑制GH反应元件的转录激活并抑制Jak2酪氨酸激酶活性。SOCS-2有两种相反的作用：在低浓度时，它抑制GH诱导的STAT5依赖性基因转录，但在高浓度时可观察到GH信号的恢复。在共转染研究中，SOCS-2能够阻断SOCS-1对GH信号传导的抑制作用，但不能阻断SOCS-3的抑制作用。这些发现表明，SOCS-2的主要功能是通过克服其他内源性SOCS分子的初始抑制作用来恢复对GH的敏感性。
