NFATc1 activity regulates the expression of myocilin induced by dexamethasone.
NFATc1 activity regulates the expression of myocilin induced by dexamethasone.
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DOI：
10.1016/j.exer.2014.11.009
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发表时间：
2015-01
影响因子：
3.4
通讯作者：
Peters, Donna M.
中科院分区：
文献类型：
--
作者：
Faralli, Jennifer A.;Clark, Ross W.;Filla, Mark S.;Peters, Donna M.
myocilin基因（MYOC）突变占青少年开角型青光眼病例的10%和成人原发性开角型青光眼病例的3-4%。它是一种在许多眼和非眼组织中发现的分泌性糖蛋白，与眼内压升高有关。在人小梁网（HTM）细胞中，MYOC表达可由糖皮质激素地塞米松（DEX）诱导。在这项研究中，我们研究了钙调神经磷酸酶/NFATc 1（活化T细胞的核因子）途径在DEX诱导HTM细胞MYOC中的作用。在用500 nM DEX或0.1%乙醇（EtOH;载体对照）处理0-6天的融合后HTM细胞中，当DEX存在时，MYOC的蛋白质和mRNA水平均增加。在去除DEX后，蛋白质和mRNA水平在另外12天内保持升高。仅1天的DEX处理就足以引发MYOC mRNA的持续增加，其在去除DEX后持续4天。与其他研究类似，直到DEX处理的第二天才观察到肌球蛋白表达，而mRNA在DEX的一天内增加，表明这是继发性糖皮质激素应答。为了确定MYOC基因表达是否受钙调磷酸酶/NFATc 1调节，在加入DEX或EtOH 2天之前，用钙调磷酸酶抑制剂环孢菌素A或印加-6预处理HTM细胞1小时。NFATc 1 siRNA用于确定MYOC mRNA表达是否需要NFATc 1。还用离子霉素处理细胞以确定增加的胞质钙是否影响MYOC表达。这些研究表明，DEX诱导的MYOC mRNA的增加可以用CsA或印加-6或用NFATc 1 siRNA转染来抑制，并且离子霉素不能增加MYOC mRNA。还进行免疫荧光显微镜检查以确定DEX是否引起NFATc 1的核转位。免疫组化显示，NFATc 1在DEX处理后15 min内重新定位到细胞核，并在那里停留长达2 h。这些数据表明，DEX诱导的MYOC表达增加以钙非依赖性机制激活钙调神经磷酸酶和NFATc 1通路。
Mutations in the myocilin gene (MYOC) account for 10% of juvenile open-angle glaucoma cases and 3–4% of adult onset primary open-angle glaucoma cases. It is a secreted glycoprotein found in many ocular and non-ocular tissues and has been linked to elevated intraocular pressure. In human trabecular meshwork (HTM) cells, MYOC expression can be induced by the glucocorticoid dexamethasone (DEX). In this study we examined the role of the calcineurin/NFATc1 (Nuclear Factor of Activated T-cells) pathway in the DEX induction of MYOC in HTM cells. In post-confluent HTM cells treated with either 500 nM DEX or 0.1% ethanol (EtOH; vehicle control) for 0–6 days both protein and mRNA levels of MYOC were increased while DEX was present. The protein and mRNA levels remained elevated for an additional 12 days after the removal of DEX. Only 1 day of DEX treatment was sufficient to trigger a sustained increase in MYOC mRNA that lasted for 4 days after the removal of DEX. Similar to other studies, myocilin protein expression was not seen until the second day of DEX treatment while mRNA increased within one day of DEX indicating that this is a secondary glucocorticoid response. To determine if MYOC gene expression was regulated by calcineurin/NFATc1, HTM cells were pre-treated for 1 h with the calcineurin inhibitors cyclosporin A or INCA-6 prior to the addition of DEX or EtOH for 2 days. NFATc1 siRNA was used to determine if NFATc1 was required for MYOC mRNA expression. Cells were also treated with the ionophone ionomycin to determine if increased cytosolic calcium affected MYOC expression. These studies showed that the DEX induced increase in MYOC mRNA could be inhibited with either CsA or INCA-6 or by transfection with NFATc1 siRNA and that ionomycin was unable to increase MYOC mRNA. Immunofluorescence microscopy was also performed to determine if DEX caused the nuclear translocation of NFATc1. Immunostaining showed that NFATc1 relocated to the nucleus within 15 min of DEX treatment and remained there for up to 2 h. The data suggest that the DEX-induced increase in MYOC expression activates a calcineurin and NFATc1 pathway in a calcium independent mechanism.
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DOI：
10.1016/j.bbamcr.2013.09.020
发表时间：
2013-12
影响因子：
5.1
作者：
Faralli, Jennifer A.;Gagen, Debjani;Filla, Mark S.;Crotti, Tania N.;Peters, Donna M.
通讯作者：
Peters, Donna M.
影响因子：
2.3
作者：
Goldwich, Andreas;Scholz, Michael;Tamm, Ernst R.
通讯作者：
Tamm, Ernst R.
影响因子：
3.4
作者：
Filla, MS;David, G;Peters, DM
通讯作者：
Peters, DM
影响因子：
2.1
作者：
Park, Bum-Chan;Tibudan, Martin;Yue, Beatrice Y. J. T.
通讯作者：
Yue, Beatrice Y. J. T.
影响因子：
64.5
作者：
LIU, J;FARMER, JD;SCHREIBER, SL
通讯作者：
SCHREIBER, SL