Wound-induced p38MAPK-dependent histone H3 phosphorylation correlates with increased COX-2 expression in enterocytes
Wound-induced p38MAPK-dependent histone H3 phosphorylation correlates with increased COX-2 expression in enterocytes
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DOI：
10.1002/jcp.20626
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发表时间：
2006-06-01
影响因子：
5.6
通讯作者：
Jobin, C
中科院分区：
文献类型：
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作者：
Karrasch, T;Steinbrecher, KA;Jobin, C
胃肠道上皮细胞损伤触发了一个重要的生物反应，称为恢复，一个旨在使受伤区域上皮再生的过程。不幸的是，很少有人知道的内在分子信号事件牵连在这个主机的反应。我们假设，受伤的肠上皮细胞激活信号通路，导致染色质修饰和考克斯-2上调恢复过程中。使用移液管尖端通过多个平行划痕对汇合的大鼠IEC 18细胞进行机械损伤。使用特异性磷酸化抗体通过蛋白质印迹法测定NF-κ B（Ser 536）、p38和组蛋白H3（Ser 10）（H3 S10）磷酸化。RT-PCR、Western Blot和ELISA检测考克斯-2基因表达。通过染色质免疫沉淀（ChIP）评价磷酸化H3、ReIA（NF-κ B）和RNA聚合酶11与考克斯-2基因启动子的关联。特异性抑制剂Bay 11 -7082和SB 239063以及Ac 15 kappa B-超阻遏物（Ad 5 I kappa BAA）和Ad 5 dnp 38分别用于阻断NF-κ B-和p38-信号通路。创伤诱导肠细胞中RelAS 536、H3 S10和p38 MAPK快速且持续（24小时）磷酸化。对考克斯-2基因启动子的ChIP分析表明存在磷酸化-H3 S10以及ReIA和RNA聚合酶11的募集，该过程被SB 239063阻断。最后，NF-κ B（Ad 5 I κ BAA）或p38 MAPK（Ad 5 dnp 38）信号传导的分子阻断强烈抑制肠上皮细胞的恢复。p38 MAPK依赖的组蛋白3磷酸化是肠创伤愈合反应的重要组成部分。选择性参与愈合/恢复的靶向信号通路可能提供一种新的手段来维持或重建宿主肠道屏障的完整性。
Gastrointestinal epithelial cell damage triggers an important biological response called restitution, a process aimed at reepithelializing the Wounded areas. Unfortunately, little is known about the intrinsic molecular signaling events implicated in this host response. We hypothesized that wounding intestinal epithelial cells activates signaling pathways leading to chromatin modification and COX-2 upregulation during restitution. Confluent rat IEC18 cells were mechanically wounded by Multiple parallel scratches using a pipet tip. NF-kappa B(Ser536), p38, and histone H3(Ser10) (H3S10) phosphorylation were determined by Western blot using specific phospho-antibodies. COX-2 gene expression was evaluated by RT-PCR, Western Blot, and ELISA. Association of phosphorylated H3, ReIA (NF-kappa B), and RNA polymerase 11 to the COX-2 gene promoter was evaluated by chromatin immunoprecipitation (ChIP). The specific inhibitors Bay11-7082 and SB239063 as well as Ac15 kappa B-superrepressor (Ad5I kappa BAA) and Ad5dnp38 were used to block NF-kappa B- and p38-signaling pathways, respectively. Wounding induced a rapid and sustained (24 h) phosphorylation of RelAS536, H3S10, and p38MAPK in enterocytes. ChIP analysis of the COX-2 gene promoter demonstrated the presence of phospho-H3S10 and recruitment of ReIA and RNA polymerase 11, a process blocked by SB239063. Finally, molecular blockade of NF-kappa B (Ad5I kappa BAA) or p38MAPK (Ad5dnp38) signaling strongly inhibited enterocyte restitution. p38MAPK-dependent histone 3 phosphorylation is an important component of the intestinal wound-healing response. Targeting-signaling pathways selectively involved in healing/restitution may provide a novel means to maintain or re-establish host intestinal barrier integrity.