PDCD10 (CCM3) regulates brain endothelial barrier integrity in cerebral cavernous malformation type 3: role of CCM3-ERK1/2-cortactin cross-talk.
PDCD10 (CCM3) regulates brain endothelial barrier integrity in cerebral cavernous malformation type 3: role of CCM3-ERK1/2-cortactin cross-talk.
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DOI：
10.1007/s00401-015-1479-z
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发表时间：
2015-11
影响因子：
12.7
通讯作者：
Andjelkovic AV
中科院分区：
文献类型：
--
作者：
Stamatovic SM;Sladojevic N;Keep RF;Andjelkovic AV
脑内皮细胞屏障完整性受损是脑海绵状血管畸形(CCM)病变发展的关键。本研究探讨了人脑内皮细胞中PDCD10(CCM3)突变/缺失时紧密连接(TJ)复合体组织的变化。对CCM3突变的病变和CCM3 siRNA(CCM3-基因敲除)的脑内皮细胞的分析表明，TJ跨膜和支架蛋白的mRNA表达很少或没有增加，但蛋白水平普遍下降。CCM3基因敲除的细胞中Claudin-5和occludin从细胞膜重新分布到胞浆中，蛋白质周转率没有变化，但与ZO-1的蛋白质相互作用减弱，ZO-1与肌动蛋白细胞骨架的相互作用减弱。CCM3突变/缺失最深刻的影响是对肌动蛋白结合蛋白Cortactin的影响。CCM3缺失导致皮质肌动蛋白Ser-磷酸化，从ZO-1和肌动蛋白解离，重新分布到胞浆中并降解。这影响了皮质肌动蛋白环的组织，TJ复合体的稳定性，从而影响了屏障的完整性，持续对菊糖具有高通透性。CCM3耗竭和皮质蛋白改变之间的潜在联系是MAP激酶ERK1/2的紧张性激活。抑制ERK1/2增加了皮质蛋白的表达和整合到TJ复合体中，并改善了屏障的完整性。这项研究强调了CCM3在调节TJ复合体组织和脑内皮屏障通透性方面的潜在作用。
Impairment of brain endothelial barrier integrity is critical for cerebral cavernous malformation (CCM) lesion development. The current study investigates changes in tight junction (TJ) complex organization when PDCD10 (CCM3) is mutated/depleted in human brain endothelial cells. Analysis of lesions with CCM3 mutation and brain endothelial cells transfected with CCM3 siRNA (CCM3-knockdown) showed little or no increase in TJ transmembrane and scaffolding proteins mRNA expression, but proteins levels were generally decreased. CCM3- knockdown cells had a redistribution of claudin-5 and occludin from the membrane to the cytosol with no alterations in protein turnover but with diminished protein-protein interactions with ZO-1 and ZO-1 interaction with the actin cytoskeleton. The most profound effect of CCM3 mutation/depletion was on an actin-binding protein, cortactin. CCM3 depletion caused cortactin Ser-phosphorylation, dissociation from ZO-1 and actin, redistribution to the cytosol and degradation. This affected cortical actin ring organization, TJ complex stability and consequently barrier integrity, with constant hyperpermeability to inulin. A potential link between CCM3 depletion and altered cortactin was tonic activation of MAP kinase ERK1/2. ERK1/2 inhibition increased cortactin expression and incorporation into the TJ complex and improved barrier integrity. This study highlights the potential role of CCM3 in regulating TJ complex organization and brain endothelial barrier permeability.