Lisse Thomas S, Rieger Sandra
Davis Center for Regenerative Biology and Medicine, MDI Biological Laboratory, 159 Old Bar Harbor Road, Salisbury Cove, ME 04672, USA
The Jackson Laboratory, Bar Harbor, ME 04609, USA.
J Cell Sci. 2017 Mar 1;130(5):975-988. doi: 10.1242/jcs.197343. Epub 2017 Jan 25.
Although the functions of HO in epidermal wound repair are conserved throughout evolution, the underlying signaling mechanisms are largely unknown. In this study we used human keratinocytes (HEK001) to investigate HO-dependent wound repair mechanisms. Scratch wounding led to HO production in two or three cell layers at the wound margin within ∼30 min and subsequent cysteine modification of proteins via sulfenylation. Intriguingly, exogenous HO treatment resulted in preferential sulfenylation of keratinocytes that adopted a migratory phenotype and detached from neighboring cells, suggesting that one of the primary functions of HO is to stimulate signaling factors involved in cell migration. Based on previous findings that revealed epidermal growth factor receptor (EGFR) involvement in HO-dependent cell migration, we analyzed oxidation of a candidate upstream target, the inhibitor of κB kinase α (IKKα; encoded by ), as a mechanism of action. We show that IKKα is sulfenylated at a conserved cysteine residue in the kinase domain, which correlates with de-repression of EGF promoter activity and increased EGF expression. Thus, this indicates that IKKα promotes migration through dynamic interactions with the EGF promoter depending on the redox state within cells.
尽管血红素加氧酶（HO）在表皮伤口修复中的功能在整个进化过程中是保守的，但其潜在的信号传导机制在很大程度上尚不清楚。在本研究中，我们使用人角质形成细胞（HEK001）来研究HO依赖性伤口修复机制。划痕损伤在约30分钟内导致伤口边缘两到三层细胞中产生HO，并随后通过亚磺酰化对蛋白质进行半胱氨酸修饰。有趣的是，外源性HO处理导致采用迁移表型并与相邻细胞分离的角质形成细胞优先发生亚磺酰化，这表明HO的主要功能之一是刺激参与细胞迁移的信号因子。基于先前揭示表皮生长因子受体（EGFR）参与HO依赖性细胞迁移的研究结果，我们分析了候选上游靶点κB激酶α抑制剂（IKKα；由[具体基因名称]编码）的氧化作为一种作用机制。我们发现IKKα在激酶结构域的一个保守半胱氨酸残基处发生亚磺酰化，这与表皮生长因子（EGF）启动子活性的去抑制和EGF表达增加相关。因此，这表明IKKα通过根据细胞内氧化还原状态与EGF启动子的动态相互作用来促进迁移。
