Centre for Vascular Research, University of New South Wales, Sydney, Australia.
PLoS One. 2012;7(7):e39811. doi: 10.1371/journal.pone.0039811. Epub 2012 Jul 6.
The immediate-early gene Egr-1 controls the inducible expression of many genes implicated in the pathogenesis of a range of vascular disorders, yet our understanding of the mechanisms controlling the rapid expression of this prototypic zinc finger transcription factor is poor. Here we show that Egr-1 expression induced by IL-1beta is dependent on metalloproteinases (MMP) and a disintegrin and a metalloproteinase (ADAM). Pharmacologic MMP/ADAM inhibitors and siRNA knockdown prevent IL-1beta induction of Egr-1. Further, IL-1beta activates Egr-1 via the epidermal growth factor receptor (EGFR). This is blocked by EGFR tyrosine kinase inhibition and EGFR knockdown. IL-1beta induction of Egr-1 expression is reduced in murine embryonic fibroblasts (mEFs) deficient in ADAM17 despite unbiased expression of EGFR and IL-1RI in ADAM17-deficient and wild-type mEFs. Finally, we show that IL-1beta-inducible wound repair after mechanical injury requires both EGFR and MMP/ADAM. This study reports for the first time that Egr-1 induction by IL-1beta involves EGFR and MMP/ADAM-dependent EGFR phosphorylation.
立即早期基因 Egr-1 控制着许多与多种血管疾病发病机制相关的基因的诱导表达,然而我们对控制这种典型锌指转录因子快速表达的机制的理解还很有限。在这里,我们发现白细胞介素-1β诱导的 Egr-1 表达依赖于金属蛋白酶 (MMP) 和去整合素金属蛋白酶 (ADAM)。药理 MMP/ADAM 抑制剂和 siRNA 敲低可防止白细胞介素-1β诱导 Egr-1。此外,白细胞介素-1β通过表皮生长因子受体 (EGFR) 激活 Egr-1。这一过程被 EGFR 酪氨酸激酶抑制和 EGFR 敲低所阻断。尽管在 ADAM17 缺陷型和野生型 mEFs 中,表皮生长因子受体和白细胞介素-1RI 的表达不受影响,但缺乏 ADAM17 的小鼠胚胎成纤维细胞 (mEFs) 中,白细胞介素-1β诱导的 Egr-1 表达减少。最后,我们发现机械损伤后的 IL-1β 诱导性伤口修复需要 EGFR 和 MMP/ADAM。本研究首次报道,白细胞介素-1β诱导的 Egr-1 涉及 EGFR 和 MMP/ADAM 依赖性 EGFR 磷酸化。