Hong Pan, Lan Hainan, Li Yumeng, Fu Zhiling, Zheng Xin
College of Animal Science and Technology, Jilin Agricultural University, Xincheng Street 2888, Changchun 130118, China.
College of Animal Science and Technology, Jilin Agricultural University, Xincheng Street 2888, Changchun 130118, China.
Gen Comp Endocrinol. 2016 Apr 1;229:67-73. doi: 10.1016/j.ygcen.2016.02.022. Epub 2016 Mar 2.
Growth hormone (GH) is reportedly species-specific. Primate growth hormone can trigger non-primate growth hormone receptor (GHR), but primates GHR cannot be activated by non-primate GH. However, it is also unclear that why primate GH and non-primate GH have different biological activities. Thus, we analysed primate growth hormone (human growth hormone (hGH)) or non-primate GH (porcine growth hormone (pGH))-induced intracellular signalling in 3T3-F442A cells and rat hepatocytes in a dose- and time-dependent manner to explore the different biological activities between them. The results revealed that both hGH and pGH can activate Janus kinase 2 (JAK2), Signal transducers and activators of transcription 1, 3 and 5 (STATs 1, 3 and 5) and extracellular signal-regulated kinase 1/2 (ERK1/2). There were no significant differences in JAK2 or ERK1/2 tyrosine phosphorylation after hGH and pGH treatment, but there were different between hGH and pGH in STAT/1/3/5 tyrosine phosphorylation, and JAK2, STAT/1/3/5 tyrosine phosphorylation was time-dependent and dose-dependent, whereas ERK1/2 was not. Both hGH and pGH demonstrated similar kinetics for STATs 1, 3 and 5 phosphorylation, but the pGH-mediated tyrosine phosphorylation was weaker than that mediated by hGH. Our observations indicated that the levels of main signalling proteins phosphorylation triggered by hGH or pGH were not exactly the same, which may explain the different biological activities showed by primate GH and non-primate GH.
据报道，生长激素（GH）具有物种特异性。灵长类动物生长激素可激活非灵长类动物生长激素受体（GHR），但灵长类动物GHR不能被非灵长类动物GH激活。然而，目前尚不清楚为何灵长类动物GH和非灵长类动物GH具有不同的生物学活性。因此，我们以剂量和时间依赖的方式分析了灵长类动物生长激素（人类生长激素（hGH））或非灵长类动物GH（猪生长激素（pGH））在3T3-F442A细胞和大鼠肝细胞中诱导的细胞内信号传导，以探究它们之间不同的生物学活性。结果显示，hGH和pGH均可激活Janus激酶2（JAK2）、信号转导子和转录激活子1、3和5（STATs 1、3和5）以及细胞外信号调节激酶1/2（ERK1/2）。hGH和pGH处理后JAK2或ERK1/2酪氨酸磷酸化无显著差异，但hGH和pGH在STAT/1/3/5酪氨酸磷酸化方面存在差异，且JAK2、STAT/1/3/5酪氨酸磷酸化呈时间和剂量依赖性，而ERK1/2并非如此。hGH和pGH在STATs 1、3和5磷酸化方面表现出相似的动力学，但pGH介导的酪氨酸磷酸化弱于hGH介导的。我们的观察结果表明，hGH或pGH触发的主要信号蛋白磷酸化水平并不完全相同，这可能解释了灵长类动物GH和非灵长类动物GH所表现出的不同生物学活性。
