Severe liver degeneration and lack of NF - k B activation in NEMO/IKK g -deficient mice
Severe liver degeneration and lack of NF - k B activation in NEMO/IKK g -deficient mice
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NEMO/IKK g 缺陷小鼠的严重肝变性和缺乏 NF - k B 激活
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
T. Mak
中科院分区：
文献类型：
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作者：
D. Rudolph;W. Yeh;A. Wakeham;B. Rudolph;D. Nallainathan;J. Potter;A. Elia;T. Mak
I k B是NF- k B的抑制剂，其磷酸化是转录因子NF- k B激活的重要步骤。磷酸化由IKK B激酶（IKK）复合物介导，已知IKK复合物含有两个催化亚基：IKK a和IKK B。最近发现了一种新的、非催化性的激酶复合物，称为NEMO（NF- k B必需调节剂）/ IKK g.我们已经通过基因打靶产生NEMO/IKK g -缺陷小鼠。突变胚胎在E12.5-E13.0死于细胞凋亡引起的严重肝损伤。NEMO/ IKK g缺陷的原代鼠胚胎成纤维细胞（MEF）缺乏可检测的响应TNF α、IL-1、LPS和Poly（IC）的NF-κ B DNA结合活性，并且不显示刺激依赖性的I κ B激酶活性，这与I κ B α缺乏磷酸化和降解相关。与这些数据一致，突变MEF显示出对TNF α诱导的细胞凋亡的敏感性增加。我们的数据提供了体内证据，NEMO/IKK g是IKK复合物的第一个重要的非催化成分。用BamHI消化的基因组DNA与外侧探针杂交，通过Southern印迹分析鉴定和确认了突变体，该探针检测野生型基因座的6-kb条带和突变等位基因的3-kb条带。使用neo基因的探针确认单一整合。三次正确的ES进入，所有三次都是通过使用尾跟随成功执行的
Phosphorylation of I k B, an inhibitor of NF- k B , is an important step in the activation of the transcription factor NF- k B . Phosphorylation is mediated by the I k B kinase (IKK) complex, known to contain two catalytic subunits: IKK a and IKK b . A novel, noncatalytic component of this kinase complex called NEMO ( NF- k B essential modulator)/ IKK g was identified recently. We have generated NEMO/IKK g -deficient mice by gene targeting. Mutant embryos die at E12.5–E13.0 from severe liver damage due to apoptosis. NEMO/ IKK g -deficient primary murine embryonic fibroblasts (MEFs) lack detectable NF- k B DNA-binding activity in response to TNF a , IL-1, LPS, and Poly(IC) and do not show stimulus-dependent I k B kinase activity, which correlates with a lack of phosphorylation and degradation of I k B a . Consistent with these data, mutant MEFs show increased sensitivity to TNF a -induced apoptosis. Our data provide in vivo evidence that NEMO/IKK g is the first essential, noncatalytic component of the IKK complex. -mercap-toethanol, Recombinants were identified and confirmed by Southern blot analysis using Bam HI-digested ge- nomic DNA hybridized to an external flanking probe, which detects a 6-kb band for the wild-type locus and a 3-kb band for the mutant allele. Single integration was confirmed using a probe to the neo gene. Three correctly ES into and all three successfully was performed by using tail following