Short form FLICE-inhibitory protein promotes TNFalpha-induced necroptosis in fibroblasts derived from CFLARs transgenic mice
Short form FLICE-inhibitory protein promotes TNFalpha-induced necroptosis in fibroblasts derived from CFLARs transgenic mice
复制标题
短形式 FLICE 抑制蛋白促进 CFLAR 转基因小鼠成纤维细胞中 TNFα 诱导的坏死性凋亡
DOI：
10.1016/j.bbrc.2016.10.015
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
H.
中科院分区：
文献类型：
--
作者：
Shindo;R. Yamazaki;S. Ohmuraya;M. Araki;K. Nakano;H.
细胞FLICE抑制蛋白（cFLIP）是起始剂半胱天冬酶（caspase 8）的无催化活性的同源物，并通过与半胱天冬酶8结合来阻断凋亡。人CFLAR基因编码两种蛋白质，由于选择性剪接，长形式cFLIP（cFLIPL）和短形式cFLIP（cFLIPs）。最近的研究表明，cFLIPs的表达，而不是cFLIPL的表达促进了永生化的人角质形成细胞系HaCaT中的程序性坏死（也称为坏死性凋亡）。在这里，我们发现cFLIPs的表达类似地促进永生化成纤维细胞的坏死性凋亡。为了进一步扩展这一观察结果，并排除角质形成细胞或成纤维细胞的永生化过程可能影响cFLIPs表达诱导的表型的可能性，我们产生了人CFLAR转基因（Tg）小鼠。与野生型（WT）成纤维细胞相比，源自CFLARs Tg小鼠的原代成纤维细胞对TNFα诱导的坏死性凋亡的敏感性增加，但不发生凋亡。此外，与TNFα刺激后的野生型成纤维细胞相比，CFLARSTg成纤维细胞中强烈诱导了坏死性凋亡的标志，如受体相互作用蛋白激酶（RIPK）1和RIPK 3的磷酸化以及混合谱系激酶结构域样（MLKL）的寡聚体形成。因此，cFLIPs依赖性促进坏死性凋亡不是永生化角质形成细胞或成纤维细胞所独有的，而且也普遍适用于原代成纤维细胞。
Cellular FLICE-inhibitory protein (cFLIP) is a catalytically inactive homolog of the initiator caspase, caspase 8 and blocks apoptosis through binding to caspase 8. HumanCFLARgene encodes two proteins, a long form cFLIP (cFLIPL) and a short form cFLIP (cFLIPs) due to an alternative splicing. Recent studies have shown that expression of cFLIPs, but not cFLIPLpromotes programmed necrosis (also referred to as necroptosis) in an immortalized human keratinocyte cell line, HaCaT. Here, we found that expression of cFLIPs similarly promoted necroptosis in immortalized fibroblasts. To further expand this observation and exclude the possibility that immortalization process of keratinocytes or fibroblasts might affect the phenotype induced by cFLIPs expression, we generated humanCFLARstransgenic (Tg) mice. Primary fibroblasts derived fromCFLARsTg mice were increased in susceptibility to TNFα-induced necroptosis, but not apoptosis compared to wild-type (WT) fibroblasts. Moreover, hallmarks of necroptosis, such as phosphorylation of receptor-interacting protein kinase (RIPK)1 and RIPK3, and oligomer formation of mixed lineage kinase domain-like (MLKL) were robustly induced inCFLARsTg fibroblasts compared to wild-type fibroblasts following TNFα stimulation. Thus, cFLIPs-dependent promotion of necroptosis is not unique to immortalized keratinocytes or fibroblasts, but also to generalized to primary fibroblasts.