Microtubule disassembly breaks down the barrier integrity of corneal endothelium.
Microtubule disassembly breaks down the barrier integrity of corneal endothelium.
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DOI：
10.1016/j.exer.2009.03.019
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发表时间：
2009-09
影响因子：
3.4
通讯作者：
Srinivas, Sangly P.
中科院分区：
文献类型：
--
作者：
Jalimarada, Supriya S.;Shivanna, Mahesh;Kini, Vidisha;Mehta, Dolly;Srinivas, Sangly P.
关键词：
连接周围肌动球蛋白环（PAMR）的收缩性增加会破坏角膜内皮的屏障完整性。本研究探讨了微管解体对肌球蛋白轻链（MLC）磷酸化的影响，肌动球蛋白收缩的生化标志物，以及培养的牛角膜内皮细胞（BCEC）单层屏障的完整性。暴露于容易诱导微管分解的诺考达唑，导致皮质肌动蛋白细胞骨架在顶端连接复合物处的特征性致密组装的破坏（即，PAMR）和ZO-1从其正常基因座的分散。诺考达唑还导致MLC磷酸化的增加。伴随着这些变化，诺考达唑引起HRP和FITC葡聚糖（10 kDa）的渗透性增加和跨内皮电阻（TER）的降低。Y-27632（Rho激酶抑制剂）和毛喉素（已知通过直接升高cAMP抑制RhoA的活化）对抗诺考达唑诱导的MLC磷酸化、TER降低和ZO-1分散。破坏BCEC单层屏障完整性的凝血酶也诱导微管解体和MLC磷酸化。用紫杉醇预处理以稳定微管对抗凝血酶作用。这些结果表明，微管解体打破了BCEC的屏障完整性，通过激活RhoA和随后的破坏PAMR。凝血酶效应还强调了GPCR下游的信号传导也可以影响微管的组织。
Increased contractility of the peri-junctional actomyosin ring (PAMR) breaks down the barrier integrity of corneal endothelium. This study has examined the effects of microtubule disassembly on Myosin Light Chain (MLC) phosphorylation, a biochemical marker of actomyosin contraction, and barrier integrity in monolayers of cultured bovine corneal endothelial cells (BCEC). Exposure to nocodazole, which readily induced microtubule disassembly, led to disruption of the characteristically dense assembly of cortical actin cytoskeleton at the apical junctional complex (i.e., PAMR) and dispersion of ZO-1 from its normal locus. Nocodazole also led to an increase in phosphorylation of MLC. Concomitant with these changes, nocodazole caused an increase in permeability to HRP and FITC dextran (10 kDa) and a decrease in trans-endothelial electrical resistance (TER). Y-27632 (a Rho kinase inhibitor) and forskolin (known to inhibit activation of RhoA through direct elevation of cAMP) opposed the nocodazole-induced MLC phosphorylation, decrease in TER, and dispersion of ZO-1. Thrombin, which breaks down the barrier integrity of BCEC monolayers, also induced microtubule disassembly and MLC phosphorylation. Pretreatment with paclitaxel to stabilize microtubules opposed the thrombin effects. These results suggest that microtubule disassembly breaks down the barrier integrity of BCEC through activation of RhoA and subsequent disruption of the PAMR. The thrombin effect also highlights that signaling downstream of GPCRs can also influence the organization of microtubules.
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DOI：
10.1083/jcb.200612080
发表时间：
2007-03-12
期刊：
The Journal of cell biology
影响因子：
--
作者：
Ikenouchi J;Umeda K;Tsukita S;Furuse M;Tsukita S
通讯作者：
Tsukita S
影响因子：
2.8
作者：
Funaki, T;Nakao, A;Kanai, A
通讯作者：
Kanai, A
影响因子：
4.8
作者：
Goeckeler, ZM;Wysolmerski, RB
通讯作者：
Wysolmerski, RB
影响因子：
5.5
作者：
Mehta, D;Tiruppathi, C;Malik, AB
通讯作者：
Malik, AB
影响因子：
4.8
作者：
Birukova, AA;Birukov, KG;Verin, AD
通讯作者：
Verin, AD